Title of Invention

METHOD FOR INCREASING STANDBY BATTERY LIFE OF A MOBILE DEVICE

Abstract This invention relates to a method and system for increasing the standby battery life of a GSM mobile device. The present invention comprises a method for increasing the standby battery life of a GSM mobile device by reducing monitoring of the serving cell's paging messages using a deterministic and adaptive procedure with zero impact on call performance, where the said procedure reduces the frequency of reception of valid paging messages, intended for the said device in the Paging Channel, by lengthening paging-read interval.
Full Text FORM 2
THE PATENTS ACT,
1970 [39 of 1970]
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(Section 10; Rule 13)
A METHOD AND SYSTEM FOR INCREASING THE STANDBY BATTERY
LIFE OF A GSM MOBILE DEVICE
SAMSUNG INDIA SOFTWARE OPERATIONS PRIVATE LIMITED
BAGMANE LAKEVIEW, BLOCK 'Br,
No. 66/1, BAGMANE TECH PARK,
C V RAMAN NAGAR,
BYRASANDRA, BANGALORE - 560093
A Wholly Owned Subsidiary
Of Samsung Electronics Company Limited, Korea
[An Indian Company]
The following Specification particularly describes the invention and the
manner in which it is to be performed
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FIELD OF INVENTION
The invention relates, in general, to the field of cellular wireless communication system which implements the principle of paging channels, hereafter referred to as the PCH, to gain dedicated attention of the served mobile units and wherein the served mobile units are required to monitor the PCH at regular intervals to watch out for all occasions of the wireless communication system's desire to gain dedicated attention, particularly to receive incoming calls or to receive a short message. More particularly, this invention relates to a method and system for increasing the standby battery life of a GSM mobile device.
DESCRIPTION OF RELATED ART
Since the invention of the first wireless cellular phone, cellular-technology has become the preferred standard for portable wireless communication system across the world. A cellular communications system is usually represented as a honeycombed structure, as indicated in Figure 1. Each such hexagonal structure is referred to as a “cell”, in the parlance of cellular technology. Each of these cells is equipped with a Radio Transmitter and a Radio Receiver, collectively known as a Base Transceiver Station, hereafter referred to as the BTS. Each such cell has a range of operation over which it caters to a plurality of stationary or roaming mobile unit users. The plurality of such constituent cells spans the entire geographic region thereby providing a full coverage to all the mobile unit users in the entire region. At any point of time, however, a particular mobile unit gets serviced by a unique cell or BTS, as would be evident to anyone skilled at the related art. The same has been indicated in the Figure 1. It would be apparent to those skilled in the related art that only those aspects of the BTS which are germane to the present invention has been elucidated in the Figure 1, omitting all the other irrelevant intricacies.
The idle-mode behaviour of a mobile unit can be written off generically as follows:
1: Looking out for notifications, a.k.a. paging messages, from the Network indicating an incoming call or a short message by reading information out off the PCH.
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2: Gathering the received signal strength, known in the prior art as Received Signal Strength Indication and hereafter referred to as RSSI, of the serving cell.
3: Scanning the plurality of neighboring cells, surrounding the mobile unit, and gathering the RSSI for each of them.
4: Evaluating if there is/are any neighbor cell/cells which has/have a higher RSSI compared to the serving cell's RSSI and then making a reselection to the best neighboring cell, among the plurality of neighbor cells having higher RSSI than the serving cell, subject to certain timing constraints. Once reselected, the steps 1 through 4 are repeated in the new cell.
The quality with which the mobile unit is able to meet the first objective of the idle-mode behavior determines the service quality of the cell for that particular mobile unit. A mobile unit is considered to be having good service quality from the serving cell if it is able to decode the NW-transmitted information on the PCH without too many failures and vice-versa.
The standby battery life of a mobile unit is a direct function of the above four steps [1] through [4] as significant amount of battery is consumed in the process of tuning the Radio Frequency Antenna Unit, hereafter referred to as the RF unit, and receiving data from the downlink beacon frequency. The average standby time of a mobile unit can be expressed as follows: Standby Time (in hours) = [(Battery Capacity in milliampere-hours) / (Average Current consumed in milliampere)]
From the perspective of wireless communication protocols, the chief contributing cause to this average current consumption is the operation of the RF unit to monitor, read and/or scan the radio frequencies to achieve the above four idle-mode goals. RF unit activity in the idle mode can be summarized in the equation below:
RF unit activity in idle mode =
RF reception on the serving cell's PCH data blocks and gathering
RSSI of the same
+
RF scanning of the neighbor cell's radio frequency to obtain the respective RSSIs
In light of above equation, it is apparent that any battery conservation needs
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to be clone by optimizing one or both of the above two factors.
Work clone in the prior art has indicated several ways to optimize on the aspect of neighbor cell scanning by reducing the rate at which the neighbor cells are scanned based on certain factors and thereby reducing the RF unit usage, and hence the current consumption, over a period of time. An application filed on by the assignee of the current invention has suggested a novel “Scan Suspension Criterion” in the Indian Patent Application to reduce the monitoring of the neighbor cells and also reduce the number of reselections.
A mobile unit is also required to monitor its own PCH periodically to look out for any instance of an incoming call. It is network's responsibility to forward the notification of an incoming call to the mobile unit and the network achieves the same by sending the notification in the PCH, as a paging message, at predetermined locations in the PCH which the mobile unit is also aware of. A mobile unit knows, in advance, the locations in the PCH where the NW would send the notification for an incoming call. The location or the scheduling of the notification in the PCH is determined and agreed upon between the NW and the mobile unit. The mobile unit evaluates the scheduling period autonomously by making use of certain standard network parameters like BS_PA_MFRMS, in GSM, and SCI, in CDMA.
Since an incoming call to a mobile unit can arrive practically anytime, the mobile unit is required to read the data sent in the PCH, at its pre-determined intervals, every time to check if there is an incoming call intended for it. Furthermore, since the wireless communication system does not wish to have a poor MT-call performance, it imposes strict rules on the reception of the paging messages in the PCH. In 102 of Figure 2, we show the downlink BCCH carrier or the beacon frequency of a GSM cell. This carrier carries the paging information in the Paging Channels, indicated by the label “PCH”. In 103 of Figure 2, we show the aspect of discontinuous reception or DRX, as known in the parlance of GSM which will be apparent to anyone skilled in the art. By way of DRX, the mobile unit determines the periodic interval at which it needs to read the data off the PCH. During the remainder of the time, it shuts down the RF unit and attempts to save battery. This periodic interval is decided upon by the parameter BS_PA_MFRMS, in GSM, and the mobile units are required to read the PCH data periodically. In 103 of Figure 2, we
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illustrate a scenario where the NW had used a BS_PA_MFRMS of 5. The mobile units are apprised of the same and they wake up periodically to read the respective paging messages. In the parlance of CDMA, this DRX is replaced with the concept of Slot Cycle Index (SCI). In 103 of Figure 2, we have shown that the mobile unit reads off its own paging message data from the PCH block 2, indicated by PCH2, present on the 0th multi-frame. Following that, the mobile unit shuts down its RF unit for all the PCH blocks occurring in the 1st, 2nd, 3rd and 4th multi-frame. The mobile unit subsequently reads the next instance of paging message from the PCH block 2 once again present on the 5th multi-frame. It is to be noted that the paging message may or may not have notification of an incoming call. If there is a notification of an incoming call, the mobile unit prepares itself for the call and starts a dedicated connection with the NW. If not, the mobile unit discards the paging message and awaits the next instance of the paging message.
Whenever there is an incoming call for a mobile unit, the NW sends the notification of the incoming call to the mobile unit by paging the mobile unit, using its identity, inside the appropriate PCH block. The mobile unit is expected to listen to all instances of its appropriate periodic paging message and respond to the incoming call, if any. However, it is not guaranteed that the mobile unit will be able to decode a particular paging message, containing the notification of the incoming call, in the very first attempt. The NW, therefore, sends the incoming call notification to the mobile unit once again in the next periodic interval. Typically, the NW sends the notification for that single incoming call to the mobile unit a maximum of K times, hereafter referred to as MAX_PAGE_REPEAT_FACTOR, before giving up. The value of this MAX_PAGE_REPEAT_FACTOR is dependent on the NW and varies from NW to NW. There is no technique, present in the specifications, to enable the mobile unit to obtain the said parameter nor does the NW specify this information to the mobile units.
Work done by Sang-Seo, Lee in the US patent 6,628,972 illustrated the concept of lengthening the Slot Cycle Index of a CDMA based mobile unit so that reading of the paging messages in the PCH messages are done less frequently compared to what the specifications had mandated for a given periodic interval. Mapped to the domain of GSM, the same idea would indicate lengthening the DRX period whereby the mobile unit will skip its assigned PCH read intervals, as indicated by BS_PA_MFRMS, and, instead,
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read its paging messages alternately or an integral multiple of BS_PA_MFRMS. Skipping the valid PCH reads alternately will bring down the battery usage by a close 50 percent. Skipping more will further reduce the battery usage. But the scheme proposed by the above US patent does not suggest a comprehensive and an efficient mechanism to achieve the same thereby warranting several loopholes and performance impacts. Some of the drawbacks of the above patent are: a) Un-deterministic approach which could result in poor MT-call performance with frequent call misses and b) Non-adaptive approach resulting in higher probability of missing MT-calls in a sub-optimal signal condition area, where we cannot afford to miss even one paging message.
The current invention attempts to provide “deterministic” and “adaptive” elements into the above US patent 6,628,972 to create a methodology which will result in reducing the battery usage by 50 percent, or more, without any impact on the MT-call performance on the UE, thereby allowing the methodology to be used throughout the usage period of the phone and cumulatively increasing the battery life of the phone as a continuous process, and not as an user option when the user is expecting calls rarely, as indicated in the above US patent.
Limitations
The prior art, as exemplified by the US patent 6,628,972, introduces the concept of lengthening the Slot Cycle Index (SCI) or the DRX interval, pertaining to GSM standards, in an arbitrary manner without any deterministic approach. In the prior art, the approach relied on obtaining a time interval from the user of the mobile unit when the user wanted to use the mobile phone only rarely. When the time interval started, the mobile unit increased the SCI or the DRX two times or three times or ‘N’ number of times, thereby skipping N successive paging messages which it was supposed to have read as per protocol specifications. Let the number of skip attempts be ACTUAL_SKIP_FACTOR. The user still expects to receive calls, albeit rarely. Whenever there is an incoming call, the NW sends the paging message, indicating the incoming call, a multiple number of times, ranging from 1 to a deterministic number of times, MAX_PAGE_REPEAT_FACTOR. If the SCI or the DRX interval is lengthened to a value “ACTUAL_SKIP_FACTOR” and if ACTUAL_SKIP_FACTOR is greater than MAX_PAGE__REPEAT_FACTOR,
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the mobile unit will miss an incoming call as it had skipped all those instances of paging messages when the NW was actually sending an incoming call notification. The prior art technique had made no attempt to factor in this aspect into its procedure thereby yielding a battery saving technique with a severe performance-hit loophole. There is need for a deterministic range for the selection of the value for ACTUAL_SKIP_FACTOR, and should not be left to a blind selection. A range in the form of {0, MAX_PAGE_SKIP_ATTEMPT} is required. Furthermore, the word “rarely” has a very hazy concept in the technical domain. There can be just two kinds of expectations of a user: (a) either the user expects calls or (b) the user does not expect any calls. If (a), the mobile unit must ensure that it does not miss a single incoming call. If (b), the mobile unit can as well go into a deep-sleep, as would be apparent to those in the related art, mode and save battery tremendously. When we say that the user is expecting calls “rarely”, we implicitly indicate that the user expects calls and hence, for all practical purposes, falls under the case (a). Given this expectation, we cannot just skip the reading of paging messages in an un-deterministic manner, based on a time interval. We cannot compromise with the call performance of the mobile unit.
Additionally, the prior art technique had not suggested any means of determining what that MAX_PAGE_REPEAT_FACTOR could possibly be resulting in the non-deterministic approach. If the mobile unit could get an accurate estimate of the MAX_PAGE_REPEAT_FACTOR, it could fine tune its selection of ACTUAL_SKIP_FACTOR value such that battery is saved all the time as long as the performance does not take a hit. The blind selection of the ACTUAL_SKIP_FACTOR is wrought with severe side-effects, as mentioned in the preceding section. Furthermore, there is no wireless communication system, known in the prior art, which attempted to provide information about the MAX_PAGE_REPEAT_FACTOR to its catered mobile unit. The element of NW-assisted battery saving by transferring the paging repetition factor and the pattern in which the pages would be transmitted is missing in the prior art.
There is yet another important aspect missing in the prior art technique of lengthening the DRX interval or the SCI interval, which makes the approach susceptible to low signal conditions or varying signal conditions thereby resulting in sub-optimal MT-call performance. Let us assume that the prior art
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decided to use ACTUAL_SKIP_FACTOR of 1. This means that the mobile unit will now read its own valid paging messages alternately. Let us also assume that the mobile unit is roaming in an area where the signal conditions are not too good. The mobile unit reads the first paging message and finds out that there is no incoming call for itself. The mobile unit also got an estimate of the air interface, RSSI and SNR, and found that it is not too good. As per techniques in prior art, the mobile unit blindly skips the next paging message to facilitate the battery saving process. Let us assume that there was an incoming call at this instant and the NW had sent the notification to the mobile unit on that paging message. The mobile unit could have decoded the paging message at this instant, but it had skipped. The NW would send the notification once again in the subsequent paging message. But as the signal conditions were not good, the mobile unit failed to decode the paging message in this attempt and the subsequent ones too. This leads to a miss of an MT call. The prior art techniques, employing blind paging skips, thereby fails to account for the deteriorating signal conditions and compromises with the performance to save battery. Such kind of a scenario is not unlikely in the life of a mobile unit, especially when the mobile unit is wandering through a high-interference region.
The drawback, as evident from the preceding discussion, is the failure of the prior art technique to factor in sub-optimal signal conditions. No attempt had been made in the prior art technique to intelligently handle the battery-saving procedure when the signal conditions became bad or is in the process of deterioration. In such signal conditions, the mobile unit cannot afford to miss a single paging message as it has no guarantee about its success in decoding the next paging messages.
Absence of the “deterministic” and the “adaptive” nature makes the technique in the prior art open to severe possible side effects. In this invention, a scheme is suggested, and claimed as embodiments of invention, whereby the mobile unit will save battery by lengthening the DRX interval only as long as it can do so without compromising on the MT-call performance. The decision will be very deterministic by a clever estimation, sufficiently accurately and autonomously inside the mobile unit, of the NW’s MAX_PAGE_REPEAT_FACTOR. Technically speaking, the mobile unit will implement an equation, claimed as a preferred embodiment of this invention, which will enable the mobile unit to estimate the logic employed by the NW
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BTS cells to repeat the incoming call notifications.
Furthermore, the entire battery saving process would be feedback controlled using a precise estimation of the air interface environment, once again to ensure zero compromise on MT-call performance.
SUMMARY OF THE INVENTION
It is an objective of the present invention to suggest a novel deterministic scheme to implement the already conceptualized idea of lengthening of the paging-read interval, such that the lengthening process does not make the mobile unit compromise with its MT call performance by ensuring zero incoming call misses during the time battery saving algorithm is running.
It is another objective of the present invention to suggest a method or an apparatus by way of which the mobile unit would be able to estimate, with high degree of accuracy, the repetition attempts, of an incoming call notification, which a GSM wireless communication NW is employing; the said method or the apparatus is presented in the form of an equation which the mobile unit would be able to execute autonomously and derive the repetition number.
It is yet another objective of the present invention to make use of the knowledge, gained by deriving the number of times the NW would send notification, for an incoming call, to the mobile unit, to decide how long the paging-read interval could be lengthened without affecting the MT-call performance. The knowledge of the notification repetition number would be achieved deterministically, using the invented equation, and thereby the decision process for lengthening the paging-read interval would be highly deterministic.
It is also an objective of the present invention to suggest a signal condition sensitive approach to implement the said “battery saving technique of reducing paging reception by lengthening of the paging-read interval”. Alternately stated, the objective is to ensure that the idea of lengthening the paging-read interval is not done blindly but by a careful analysis of the signal conditions to eliminate the drawbacks identified in the preceding discussion.
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It is yet another objective of the present invention to suggest an addition in the protocol standards of the existing wireless communication systems whereby the said system will provide additional information to the served mobile units, in a given cell, which will help the mobile units to know the exact incoming-call notification repetition number and the pattern in which the notifications would be transmitted across in the downlink Paging Channels. Knowledge of the exact repetition number and the pattern of transmission will enable the mobile units to have a stronger deterministic scheme.
Finally, it is an objective of the present invention to introduce a comprehensive method and a procedure, which combines the said deterministic scheme and the said signal condition feedback-controlled scheme, for saving of battery in the idle mode, of a GSM wireless device, by implementing the concept of lengthening of DRX interval or the paging-read interval as illustrated in the work of US patent 6,628,972 and in the process, simultaneously eliminating the identified drawbacks of the prior art.
The method and the procedure would be highlighted in the context of a GSM wireless device and GSM wireless communication system. Those skilled in the related art would appreciate the fact that the same rational could be extended easily to any other wireless communication systems to achieve the same results, without any significant digression from the present invention.
Accordingly, the present invention comprises a method for increasing the standby battery life of a GSM mobile device by reducing monitoring of the serving cell's paging messages using a deterministic and adaptive procedure with zero impact on call performance, where the said procedure reduces the frequency of reception of valid paging messages, intended for the said device in the Paging Channel, by lengthening paging-read interval.
These and other objects, features and advantages of the present invention will become more apparent from the ensuing detailed description of the invention taken in conjunction with the accompanying drawings.
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BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 shows a typical GSM cellular system. Each cell is equipped with a BTS and serves to a certain number of mobile units. All these cells are connected to a BSC or an MSC herein referred to as MTSO.
Figure 2 shows a typical GSM downlink beacon carrier.
Figure 3 shows the control flow, elucidated as a flow chart, to implement the invention and achieve the said benefits of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The preferred embodiments of the present invention will now be explained with reference to the accompanying drawings. It should be understood however that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. The following description and drawings are not to be construed as limiting the invention and numerous specific details are described to provide a thorough understanding of the present invention, as the basis for the claims and as a basis for teaching one skilled in the art how to make and/or use the invention. However in certain instances, well-known or conventional details are not described in order not to unnecessarily obscure the present invention in detail.
The invention relates to cellular wireless communication system which implements the principle of paging channels to gain dedicated attention of the served mobile units wherein the served mobile units are required to monitor the PCH at regular intervals to watch out for all occasions of the wireless communication system's desire to gain dedicated attention, particularly to receive incoming calls or to receive a short message.
Figure 2 describes a typical TDMA based GSM downlink beacon. Each frame is time sliced into 8 time-slots as shown in 101. In GSM system, the downlink beacon is transmitted on the 0th time-slot of the beacon frequency. 51 such frames make up a total 51-multiframe structure, as in 102, where all information is transmitted on the 0th time-slot. The CCCH blocks contain the Paging Channels or the PCH. As we can see there are 9 PCH blocks in a
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single 51-multiframe structure. A particular mobile user needs to monitor only one among the 9 blocks, the determination of which can be done autonomously inside the mobile unit using well-known equations, as would be apparent to anyone skilled in the related art. In 103, we show a paging periodicity interval of 5. That is, BS_PA_MFRMS is 5 indicating that the paging block for the mobile unit comes after 5 such 51-multiframes. The mobile unit reads its paging message from the Olth-multiframe and then skips the next 4 multi-frames and re-reads the appropriate PCH block, out of the 9 available PCH blocks, in the 5th multi-frame. This interval would be referred to as the “paging-read interval”, in the remainder of the document. During the remaining time, the mobile unit shuts down its plurality of power consuming circuitries and saves battery. This behaviour is known as DRX, in the existing GSM domain. If there is an incoming call for a particular mobile unit, or if the NW wishes to establish a dedicated connection with a particular mobile unit, the NW would encapsulate the identity of the mobile unit in the downlink paging message and send it across in the appropriate PCH block, as shown in 102 of Figure 2, in the appropriate multi-frame, as indicated in 103 of Figure 2. The concerned mobile unit reading all instances of its downlink paging messages will find its own identity in the message and it would start the process of accessing the NW using certain other standard protocol specifications. Remainder of the times, when the NW has not encapsulated the identity of the mobile unit in the paging message, it can simply discards the message; however, only after reading it, in the first place. Based on the preceding discussion, the importance and the need of reading the downlink paging messages should have become apparent, at this point. Any attempt to lower the frequency of reading the valid paging messages, to aid battery saving, comes with an adverse effect of missing incoming calls, if the decision-making process of lowering the reading frequency, and thereby skipping valid paging messages, is not a very well thought-of process.
The current invention describes a deterministic and adaptive method of skipping valid paging messages, to aid the battery saving process, without causing any adverse impact on the MT-call performance by ensuring that no incoming calls are missed; further, enabling the battery-saving process to be implemented without any user intervention and without need of any specific time-interval to be set by user wherein the said user expects calls only rarely. By making it a continuous battery saving process, guided by the new decision making methods, the method suggested in this invention enables the mobile
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unit to save greater amount of battery than the methods laid out in the prior art, further ensuring zero incoming call misses, at the same time.
The mobile unit further comprises of a central processing unit to execute the software logic, a set of software timers, counters, flags to implement the method, a volatile random-access memory (RAM) or a non-volatile read-only memory (ROM) to store the temporary data in digital format, a running software logic executing the given wireless communication protocol, GSM in this present example, and a digital signal processing unit to compute the air interface signal parameters and estimating the condition of the air interface environment.
The mobile unit utilizes a method to estimate, with sufficient degree of accuracy and without any additional aid of the network, the maximum number of times the network would send the notification for an incoming call before the network gives up. Let us denote this maximum notification repetition factor, per incoming call, as the MAX_PAGE_REPEAT_FACTOR. There are no techniques known in the prior art whereby the mobile unit could get the value of this factor as no wireless communication system transmits this information nor is any equation or method described by which the mobile unit could estimate the same with sufficient accuracy. As would be apparent in the foregoing discussion, the mobile unit would be able to calculate this factor autonomously by making use of an equation, which is claimed as a preferred embodiment of the invention; the said equation employing an already existing NW-transmitted parameter, BS_PA_MFRMS and finally provides the maximum possible value of the MAX_PAGE_REPEAT_FACTOR. The output of the equation provides the upper limit of the page repeat factor, i.e., the maximum times the NW would send notification for an incoming call. The equation can be written off as: MAX_PAGE_REPEAT_FACTOR = [(90 DIV BS_PA_MFRMS) DIV 4], where “DIV” represents a normal integer mathematical division. The possible values of this equation, with a mention of the typical values, would be elaborated in the sections that follow. The above equation is written in light of the GSM communication system and is claimed as a preferred embodiment of the invention. A wireless communication system of different access technology, having a different flavor of this equation but finally achieving the same objective, as mentioned herein, is within the scope of this present invention.
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The mobile unit will read one instance of its valid paging message and then it would skip a certain number of consecutive valid paging messages before re-reading. Let the maximum number of valid paging messages which the mobile unit can skip, without compromising on the MT-call performance, be denoted by MAX_PAGE_SKIP_ATTEMPT. Obviously, this maximum possible page skips should always be less than the MAX_PAGE_REPEAT_FACTOR by 1 and can be written off as: MAX_PAGE_SKIP_ATTEMPT = MAX_PAGE_REPEAT_FACTOR - 1. Also, let the actual number of consecutive paging skip attempts, which the mobile unit actually utilizes to save battery life, be ACTUAL_SKIP_FACTOR. The mobile unit resorts to the normal specifications-driven behaviour without any battery saving, if the ACTUAL_SKIP_FACTOR acquires a value of 0; the said mobile unit can set a value of this ACTUAL_SKIP_FACTOR in the following range: {0, MAX_PAGE_SKIP_ATTEMPT}. However, the actual value of the same shall be made in such a way that no opportunities exist whereby an incoming call is missed and also based on the desired extent of battery saving; the said value always falling into the range mentioned above and is left to the implementer, skilled at the related art. This method incorporates the deterministic element into the decision making process by ensuring that the value of MAX_PAGE_SKIP_ATTEMPT is always less than MAX_PAGE_REPEAT_FACTOR, evaluated from the equation. This conditional check will ensure that the mobile unit never skips pages more than the maximum number of times the NW would transmit notifications for a single incoming call.
Additionally, to incorporate the feedback-control element into the battery saving process, the said mobile unit will store the signal level, RSSI, and the signal quality, SNR, of the last received valid paging message. Let us denote the last received RSSI and the last received SNR by LAST_RX_RSSI and LAST_RX_SNR respectively. Furthermore, let the mobile unit store, in a volatile or a non-volatile storage medium implemented typically as a memory array inside the computer system of the mobile unit, the RSSI and the SNR of the past few samples wherein it had read its valid paging messages. Let the sample size be denoted by MAX_SAMPLE_SIZE, the choice of which is left to the skilled implementer. Given this sample size, the mobile unit, therefore, would have the RSSI and the SNR values of the past MAX_SAMPLE_SIZE paging messages respectively. This storage of the RSSI and the SNR of the
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past MAX_SAMPLE_SIZE paging messages will be over-written with the new samples by discarding the oldest sample, every time a new paging message sample is read off the PCH. The latest sample in this storage database would correspond to LAST_RX_RSSI and LAST_RX_SNR, as mentioned above.
Before every occurrence of a valid paging message, the mobile unit will evaluate if the LAST_RX_RSSI and the LAST_RX_SNR is above a comfort threshold MIN_RX_RSSl and MIN_RX_SNR respectively. If the comparative evaluation indicates that the last received RSSI and the last received SNR is below the comfort minimum threshold, the output of this evaluation would be such that the battery saving process is turned off to ensure that not even a single valid paging message is skipped as external signal conditions are not in favor. The mobile unit will read the coming-up paging message, without any attempt to skip the same and will continue to do so until conditions are in favor. On the other hand, if the comparative check indicates that the LAST_RX_RSSI and the LAST__RX_SNR are above the respective minimum comfort threshold, a secondary check would be made to analyze the stored RSSI and SNR values of the past MAX_SAMPLE_SIZE paging messages and observe if any continuous deterioration trend, or a negative slope, is found. This analysis would help in the prediction of the imminent degradation of service quality from the serving cell. If a deterioration trend is found, the output of this evaluation would be such that the battery saving process is turned off. The battery saving process would remained turned off until the last received RSSI and the last received SNR are found above the respective comfort minimum threshold and, additionally, the RSSI/SNR data analysis of the past MAX_SAMPLE_SIZE paging messages indicate a positive slope. This evaluation step would be invoked every time before the occurrence of a valid paging message. If this evaluation step indicates a "go-ahead", shall the mobile unit proceed with the battery-saving process, subject to paging-skip rules indicated in the preceding method, making use of the invented equation. It is to be noted that the choice of the MIN_RX_RSSI and the MIN_RX_SNR is left to the specific implemented skilled at the related art. Furthermore, the method to perform the RSSI/SNR data analysis of the past MAX_SAMPLE_SIZE paging messages is also left to the skilled implementer. A generic process, however, would be outlined in the foregoing discussion.
We now delve into the rational behind the invented equation and, subsequently, outline the general principles behind selection of certain
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values. The NW parameter BS_PA_MFRMS can range from 2 through 9, as indicated in the protocol standards. A value of 2 implies that the valid paging message, for every mobile present in that cell, repeats every 2nd multi-frame or every 470milliseconds [(51*2) frames * 4.616milliseconds per frame], whereas a value of 9 indicates the repetition every 9th multi-frame or every 2.11seconds [(51*9) frames * 4.616milliseconds per frame]. Both the extremes are wrought with drawbacks; when the minimum value is used, the mobile unit hardly gets a chance to save battery due to very frequent PCH reads thereby resulting in poor standby life and, conversely, when the maximum value is used, the battery gets saved to the maximum extent, but there is considerable delay between successive paging messages resulting in poor NW performance. The typical values used, as seen in most of the GSM networks, are 5, 6 and 7. We will use the paging periodicity parameter, BS_PA_MFRMS, to be 5 for the remainder of the discussion as an example. In 103 of figure 2, we can see the paging periodicity for a BS_PAJVIFRMS of 5.
We now explain the rational behind the invented equation, in light of the GSM standards. The protocol standard enforces that the mobile unit maintain a counter, initialized to (90 DIV BS_PA_MFRMS). To those skilled in the related art, this counter would be known as the Downlink Signaling Counter or the DSC. It is mandated that every time the mobile unit fails to decode the paging message, the counter be decremented by 4 and at every successful decoding, be incremented by 1; however, never beyond the initial value of (90 DIV BS_PA_MFRMS). Furthermore, the specifications mandate that if the DSC counter ever drops down to 0 or below, the mobile unit must leave the current cell and attempt to move into a different cell by performing the cell reselection process. The fall of this counter to 0 is an indication that the service quality in the current cell has gone below acceptable limits. Given these two clauses, the current invention realizes the fact that a particular cell of the NW, in the event of notifying an incoming call, must transmit the notification a certain maximum number of times before giving up; however, this repetition attempts is not told to the served mobile units and hence this invention attempts to find it out autonomously, inside the mobile unit. This certain maximum number of times cannot be less than the tolerance amount which the wireless communication system has imposed on the mobile unit and which the NW must conform to. In this specific example, where ‘5’ is used as the value of BS_PA_MFRMS, we understand that the DSC counter
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gets initialized to ‘18’ This enforces that the wireless communication system tolerate its constituent mobile units to have 4 (18 - 4*4 = 2) straight successive failures in decoding of the paging messages (i.e., before the DSC counter becomes less than 0) before expecting the mobile unit to move out of the current cell. Subject to this restriction, it is mandatory upon the cell of the NW to transmit notification for an incoming call a maximum of 4 times continuously before giving up, as it is possible that the mobile unit fails to decode the first three instances of the paging messages, but succeeds on the fourth, and the final, decoding attempt and responds to the incoming call. This mobile unit, thereby, executes an equation mentioned in the preceding sections, which is claimed as a preferred embodiment of the invention, whereby it can estimate the maximum number of times the NW would send the notification continuously for a single incoming call. For this specific case of BS_PA_MFRMS as 5, we find the following:
MAX_PAGE_REPEAT_FACTOR = [(90 DIV 5) DIV 4] = INTEGER (4.5) = 4, where the operator INTEGER extracts the integral value of the division. Now that we know the maximum repetition attempts of notification to be employed by the NW, we can figure out the value for the maximum possible skip of the valid paging messages which the mobile unit can resort to, without affecting the MT-call performance in any way: MAX_PAGE_SKIP_ATTEMPT = MAX_PAGE_REPEAT_FACTOR -1=3. The ACTUAL_SKIP_FACTOR to be chosen for implementation should be selected, therefore, from the set given by {0, 3}, where 0 corresponds to the default specifications-driven behaviour and 3 corresponds to the maximum possible skip attempts yielding the maximum amount of battery saving. Choice of ACTUAL_SKIP_FACTOR as 1 would reduce the current consumption to nearly half, in the ideal cases. Any other value, above 1, would cause the current consumption to drop down by more than or equal to 50 percent, in theoretical terms, thereby almost doubling the battery life. Furthermore, the range determination procedure ensures that not even a single MT-call is missed during the battery saving process. Typical ACTUAL_SKIP_FACTOR values suggested in this invention, but not restricted to, is 1 or 2. A value more than 2 would increase the battery tremendously, but the probability of the call setup time becoming higher also increases, as would be apparent to all those skilled in the related art. In the other typical BS_PA_MFRMS values of 6, 7 and 8, we can deduce the range to be {0, 2}, {0, 2}, {0, 1} respectively. As we can see, the above deterministic approach provides an upper limit to the page-skipping attempts,
17

based on the paging periodicity employed by the NW. A mobile unit employing a blind page-skipping procedure of 3 successive paging messages, as quite possible from the method in the prior art US patent 6,628,972, for a NW where the BS_PA_MFRMS is 6 or above, has an extremely high possibility of missing the MT-calls.
Also, in this specific example, we make use of the MAX_SAMPLE_SIZE to be 5, although the choice is not restricted to this value. A curve can be constructed passing through the 5 discrete points and the slope could be determined. More the number of samples, better is the estimation; but at the cost of increased complexity. The slope of the curve would indicate the trend of the air interface; a negative slope indicating an imminent degradation and a positive or zero slope indicating acceptable conditions. The choice of the MIN_RX_RSSI and the MIN_RX_SNR should be made in accordance with the RF unit sensitivity of the mobile unit, in conjunction with the reference sensitivities as laid out in the protocol specifications; the said procedure should be apparent to those skilled in the related art.
With the generic principles for selecting certain thresholds identified, we now outline the generic implementation steps, as a control flow diagram, shown in Figure 3. 101 shows the IDLE mode-Camped On state of the mobile unit. In this state, the mobile unit engages in reading the multitude of system information, hereafter referred to as the SYSINFO, which the serving cell of the network, hereafter referred to as the serving BTS, is transmitting via the downlink beacon frequency, alternately referred to as the CCCH. Among other information elements, one particular SYSINFO parameter enables the mobile unit to realize the paging interval period employed by the BTS. In the parlance of GSM, this paging interval period is identified by the parameter BS_PA_MFRMS. The mobile unit remains in the state 101 as long as the conditional check of 102 does not become TRUE; effectively, ensuring that the mobile unit has read, at least once, all the transmitted SYSINFO parameters. Upon receiving the SYSINFO parameters, the mobile unit stores each and every SYSINFO elements into a volatile memory or a non-volatile memory unit, for future use. All these SYSINFO parameters are pertaining to the particular BTS, in which the mobile unit is camped, and might be different in a different BTS. Hence, the mobile unit, during the storing process into a volatile or a non-volatile memory unit, shall store the information tagged under the particular cell and shall maintain each such information block
18

separately for each and every unique BTS. The mobile unit, during its stay in a particular cell, periodically updates the SYSINFO parameters to check if any of the information elements have changed and, if so, accordingly updates the same in the volatile or the non-volatile memory unit, wherein it had stored all instances of the information elements, read previously. The concept of periodic update of the SYSINFO parameter is an un-related discussion with respect to the current invention idea, as would be apparent to those skilled in the related art, and hence, shall be omitted going forward.
Upon receiving all the SYSINFO parameters, the mobile unit changes its state from 101 and goes to the transitory state 103, wherein it prepares for the battery saving process by calculating all the optimization parameters, in addition to initializing certain parameters. The mobile unit keeps a set of data storage variables in the volatile or the non-volatile memory unit, to aid the battery-saving process. In this state, 103, the mobile unit executes the invented equation to estimate the incoming-call notification repetition attempts, which the BTS employs. Once the repetition factor is known and stored for future use, the mobile unit evaluates the range of the page skip attempts and thereafter selects an appropriate value for the actual skip attempts which it would use, to save battery. For purposes of elucidation, we employ the BS_PA_MFRMS as 5, as can be visualized in 103 of Figure 2. The remainder of the optimization parameters is calculated as follows: MAX_PAGE__REPEAT_FACTOR = (90 DIV 5) DIV 4 = 4. MAX_PAGE_SKIP_ATTEMPT = MAX_PAGE_REPEAT_FACTOR -1=3.
We now have the deterministic range of the page skip attempts as {0, 3}. The ACTUAL_SKIP_FACTOR should be a value which must be contained in the set {0, 3}, as indicated in 103. For elucidation purposes, we choose the ACTUAL_SKIP_FACTOR as 1; effectively, it implies that the paging messages shall be read alternately. All these parameters are present as “data variables” in the volatile or the non-volatile memory unit of the computer system of the said mobile unit. Further to initialization of the parameters which aid the deterministic aspect of the invention, the mobile unit now initializes the parameters, present as “data variables” in the volatile or the non-volatile memory unit of the computer system of the mobile unit, which aid the adaptive, signal-condition sensitive aspect of the invention. The MAX_SAMPLE_SIZE determines the size of the data storage element, typically implemented as a “memory array” in the computer system of the
19

mobile unit. The array shall store the RSSI and the SNR values of the received signal during reading of the paging messages off the PCH, over the last MAX_SAMPLE_SIZE paging message samples. Every time a new RSSI/SNR sample is received the array will be updated with the same. Once the array gets filled up with MAX_SAMPLE_SIZE samples, newer samples shall be inserted, at the end of the array, by discarding the oldest sample and left shifting the entire array. Furthermore, the mobile unit shall set a threshold minimum value for the RSSI and the SNR. These two parameters, MIN_RX_RSSI and MIN_RX_SNR, will be evaluated against the last received RSSI and the last received SNR, obtained from the last-read paging message, and would determine if the mobile unit should continue with the battery-saving process. Lastly, the mobile maintains an integer counter, implemented as a “data variable” in the computer system of the mobile unit, to track the number of paging messages that have been skipped per session of battery-saving. This counter “skip_attempts” is initialized to 0.
Upon initialization of the optimization parameters, the mobile unit leaves the transitory state 103 and falls into the battery-saving state 104. This is the state which enables the mobile unit to save battery by allowing it to shut down most of its power-consuming circuitry like the RF unit, the DSP unit and the processor unit. It should be the aim of any battery-saving algorithm to return to this state as soon as possible and stay in this state as long as possible. The only thing the mobile unit does, in this state, is to compute the next occurrence of the valid paging message by making use of the paging periodicity interval, obtained in the state 101 and stored in the volatile or the non-volatile unit as BS_PA_MFRMS, and waits until that time has come. The mobile unit continues to stay in this state 104 as long as the conditional check, 105, returns FALSE or a NO. Before occurrence of the valid paging message, the conditional check in 105 returns a TRUE/YES and the mobile unit transitions to the state 106.
In the state 106, the mobile unit readies the RF unit; the DSP unit and all other associated circuitries so that it can successfully read the paging message off the PCH. Upon reading the paging message, the mobile unit evaluates if there is an incoming call notification intended for it. If found, the said mobile unit leaves this IDLE mode - Camped ON state and tries to start a dedicated connection with the network. Those skilled in the related art would know that the dedicated connection procedure is not germane to this
20

present invention and can be skipped, without any impact on the brevity of the discussion. We continue, assuming that there was no incoming call notification in the received paging message. Furthermore, the mobile unit stores the RSSI and the SNR of the received signal and updates the first sample into the storage array, whose size is given by MAX_SAMPLE_SIZE. The latest sample entered into the storage array, of size MAX_SAMPLE__SIZE, would always be the LAST_RX__RSSI and the LAST_RX_SNR; two “data variables” which store the RSSI and the SNR of the last received signal.
Upon completing the activities in the state 106, the mobile unit checks if all special pre-requisites for starting the battery-saving process have been satisfied. A typical pre-requisite, suggested in this discussion, is to ensure that the mobile unit has updated the storage array with at least a minimum of MAX_SAMPLE_SIZE samples before starting the optimization process. For a MAX_SAMPLE_SIZE value of 5, this conditional check will ensure that the mobile unit has updated the storage array with 5 past samples of RSSI/SNR, before kick-starting the battery-saving process. Any other specific pre-requisite, conjured by the skilled implementer of the algorithm, can be fitted into this conditional check. As long as the check 107 returns a FALSE/NO status, the mobile unit will return back to the battery-saving state 104 and await the occurrence of the next paging message. On the next page occurrence, the mobile unit shall, once again, transition to the 106 state and read the paging message. Subsequently, the mobile unit will update the second RSSI/SNR sample into the second array location. The mobile unit, therefore, stores 5 samples into the array, whose size we have assumed to be 5, for purposes of elucidation. The snapshot of the array, at this stage, looks as follows:


Upon satisfying all the pre-requisites of the battery-saving process, the mobile unit can be seen to transition, via the connector [1], to the state 108. This state is similar to the state 104, except for the additional conditional checks which are required to take the mobile out of this state. The mobile unit, in this state, evaluates the conditional check, as in 109, and checks if a paging message is due. If the conditional check of 109 returns a FALSE/NO, the mobile unit goes back to the state 108 and continues to save battery. However, if the conditional check of 109 returns a TRUE/YES, the mobile unit, instead of directly reading the paging message as was shown in the state 106, performs the adaptive, signal-condition sensitive check and evaluates if the battery optimization technique should be applied or not.
The conditional check of 110, therefore, evaluates whether the last received RSSI or the last received SNR, obtained from the storage array as the last stored elements Array [MAX_SAMPLE_SIZE - 1].RSSI and Array [MAX_SAMPLE_SIZE - 1].SNR, is less than MIN_RX_RSSI and MIN_RX_SNR respectively, as was initialized in the state 103. Additionally the mobile unit analyzes the entire storage array, containing the past MAX_SAMPLE_SIZE samples and strives to evaluate any deterioration trend. The actual logic of analyzing the RSSI/SNR array is left to the implementer, skilled at the related art. If the last measured RSSI is less than the threshold or the last measured SNR is less than the threshold, the conditional check 110 returns a TRUE/YES. However, if both the above checks return a FALSE, indicating that the last measured samples are more than the respective thresholds, the mobile unit performs a third level check whereby it attempts to predict any imminent degradation of service by observing the presence of a negative slope or a deterioration trend in the past MAX_SAMPLE__SIZE samples. If any one, of the three checks, returns a TRUE result, the verdict of the conditional check 110 would be a TRUE/YES and the mobile unit shall jump to the state 113, without performing any battery saving by way of skipping page messages. The output of the conditional check 110 as TRUE/YES is an indication that the mobile unit is roaming in a sub-optimal signal area where skipping valid page messages could not be afforded, for reasons mentioned previously. If, however, all the three conditional checks return a FALSE result, the verdict of the conditional check 110 would be a FALSE/NO and the mobile unit shall perform the third level conditional check, as in 111.

Reaching this conditional check 111 is an indication that the mobile unit can perform a battery saving by skipping a valid paging message, subject to the deterministic constraints. In this conditional check, the mobile unit makes the deterministic check to ensure that it does not skip more pages than required, as per the page skipping range {0, 3}, illustrated in this example. The mobile unit, therefore, checks if the actual “skip_attempts” has acquired a value equal to or greater than the ACTUAL_SKIP_FACTOR value, as selected in the state 103. It needs to be noted that the “skip_attempts” was initialized to 0 in the state 103. This check therefore returns a FALSE/NO, since skip_attempts (0) is less than the ACTUAL__SKIP_FACTOR (1, as was chosen in this example). The conditional check returns a FALSE/NO and the mobile unit transitions to the transitory state 112, where it updates the “skip_attempts” by 1 and makes it acquire the value “1” indicating that it had skipped 1 valid page message. Subsequent to this, the mobile unit transitions to the battery saving state 108. The mobile unit, at this point, had saved battery by skipping a valid paging message.
In the state 108, the mobile unit awaits the occurrence of the next valid paging message. When the conditional check 109 returns a TRUE/YES, the mobile unit shifts to the state 110 and performs the signal-condition checks once again. The verdict of this check will be the same as before, i.e., FALSE/NO as there was no update of the storage array because of the page skip procedure. The mobile unit, therefore, immediately transitions to the conditional check 111, where the mobile unit checks the “skip_attempts” against the ACTUAL_SKIP_FACTOR. This time, however, the mobile unit finds that the “skip_attempts” and the ACTUAL_SKIP_FACTOR both have acquired the same value of “1”. The conditional check in 111, therefore, returns a TRUE/YES result and the mobile unit transitions to the state 113.
In this state 113, the mobile unit performs the same actions as in the state 106. The mobile unit reads the page message off the PCH. Once again, we assume that there was no incoming call notification. The mobile unit had already filled up all the MAX_SAMPLE_SIZE locations in the storage array with the past values. The mobile unit, therefore, discards the oldest sample, Array [0].RSSI and the Array [0].SNR values, left shifts the entire array to make the Array [MAX_SAMPLE_SIZE - 1].RSSI and Array [MAX__SAMPLE_SIZE - 1].SNR available and stores the latest sample,


Finally, this state resets the variable “skip_attempts” to 0, if it was not zero already. The variable “skip_attempts” had acquired the value “1” in the last page-skip procedure. Resetting this variable to 0 enables the re-use of this variable in the next page-skip attempt. Upon performing all the actions, the mobile unit transitions to the state 108 and awaits the next valid page message occurrence.
When the next valid page message is due to occur, the mobile unit present in the state 108 passes the conditional check of 109 and reaches the conditional check of 110. We assume, at this stage, that one of the checks inside the conditional check 110 encounters a TRUE result and the verdict of 110 is a TRUE/YES. The mobile unit, therefore, stops any attempt to save battery by skipping valid paging message and transitions to the state 113 directly. In this state, it reads the paging message and once again discards the oldest sample in the array; left shifts the entire array and updates the last element of the array with the received values. The “skip_attempts” being '0' already, the mobile unit does not update the variable.
The control flow having been described in its entirety, we now indicate a sample procedure of determining the negative slope or the deterioration trend. Let the SNR values of the past 5 samples are as follows: Array [0].SNR = 7X,


Array [4].SNR = 5X, where we assume that ‘X’ is a proper dimension multiplicative constant. As known in prior art, the proper dimension of 'X' could be assumed to be in “dBm (millidecibels)”, as known in the conventional art. The above data reveals a constant deteriorating trend or a constant negative slope from the last 4 samples, albeit the individual LAST_RX_SNR comparison against the MIN_RX_SNR might have indicated a FALSE result, if the MIN_RX_SNR was fixed at 3X. Similar argument could be extended to the RSSI values, present in the array. This invention does not restrict the array analysis to the one mentioned above. Any implementer, skilled in the related art, could employ an alternate scheme for determining the trend, without digressing from the essential aspects of the invention.
The above control flow delineates the method for implementing the steps mentioned in the claims of the invention. For a GSM system, we saw that we had an equation, claimed as a preferred embodiment of the invention, to estimate the MAX_PAGE_REPEAT_FACTOR. Any other wireless communication system, warranting a different flavor of this equation, however achieving the same functionality as described herein, is within the scope of this invention. Furthermore, any wireless communication system providing the MAX_PAGE_REPEAT_FACTOR to its served mobile units, inside the SYSINFO parameters, is also covered within the scope of this invention.
Effects/Advantage(s) of the Invention
This invention incorporates an additional amount of intelligence in an existing concept of lengthening of paging-read interval to save standby-mode battery, by making the concept more robust, highly deterministic and extremely adaptive, thereby yielding a method and a procedure of saving standby-mode battery without compromising on the mobile unit’s MT-call performance. The invention illustrates a novel idea, a mathematical equation, by which an UE autonomously estimates the logic of incoming-call notification repetition number that has been implemented inside a base station.


The aspects introduced in the invention provides a method by which the mobile unit can perform the battery-saving continuously, thereby cumulatively increasing the standby time over a period of time, without any intervention of the mobile unit user. As there are no performance impacts, in terms of missing MT-calls, this method need not deserve special attention of the end-user as a compromise on call performance, as seen in the prior art. Hence no specific time-interval dependent optimization is required.
The invention introduces the concept of NW-assisted battery saving in idle mode by way of which the NW will let the mobile unit know the notification repetition attempts. The mobile units can, accordingly, adapt to reach the desired level of battery-saving. This can also be standardized in the existing protocol specifications.
Due to the deterministic and adaptive nature of the algorithm, phones can even double the battery life or even more, without a single miss of an MT-call.
It will also be obvious to those skilled in the art that other control methods and apparatus can be derived from the combinations of the various methods and apparatuses of the present invention as taught by the description and the accompanying drawings and these shall also be considered within the scope of the present invention. Further, description of such combinations and variations is therefore omitted above. It should also be noted that the host for storing the applications include but not limited to a microchip, microprocessor, handheld communication device, computer, rendering device or a multi function device.
Although the present invention has been fully described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications are possible and are apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims unless they depart there from.

GLOSSARY OF TERMS AND DEFINITIONS THEREOF
DRX: Discontinuous Reception. A technique employed in GSM wireless communication system whereby each mobile unit user is segregated into specific groups, containing several other mobile unit users. The NW broadcasts paging information, not for a particular user, but for all users in that group. The mobile units need not listen to all occurrences of Paging Channel Information blocks, instead only those which are intended for its group.
TDMA: Time Division Multiple Access. It is an access technology where a single radio frequency is time sliced, with each slice or slot given to a unique user. In GSM, the slice amount is 8 thereby enabling 8 users to be allowed into a single RF carrier. In GSM, the slot duration is 577 micro-seconds and the total frame duration, of 8 slots, is 4.616 milliseconds.
PCH: The Paging Channel. The NW broadcasts all incoming call notification in paging messages which are transmitted in information blocks contained in the logical paging channel.
CCCH: Common Control Channel. It is a logical set of channels which carries information common to all the served mobile units. Typically, system information, paging information etc are transmitted in this set of channels.
BTS: The Base Transceiver Station, which transmits the radio frequency waves that enable the wireless communication.
BSC: The Base Station Controller, which manages a group of BTS units in a given geographical area.
NW: The Fixed Network, including the BTS, BSC, MSC and all other elements which comprise the wireless communication system.
MAX_PAGE_REPEAT_FACTOR: The number of times the NW is going to send the incoming-call notification, inside the paging message for the

particular mobile unit, before giving up.
MO/MT: Mobile-originated / Mobile-terminated call. An MT-call is successful if and only if the mobile unit successfully receives the intended notification message on its paging channel.
SCI: Slot Cycle Index. Used in CDMA based systems. The NW has more than one logical Paging Channels. The SCI determines which, out of the plurality of Paging Channels, will have the paging message intended for a mobile unit. SCI is a measure of the legitimate paging-message interval.
BS_PA_MFRMS: Used in GSM based systems. This parameter acquires a value from 2-9 and determines the periodicity of a legitimate paging message for any mobile unit in the system.
MAX_PAGE_SKIP_ATTEMPT: This parameter indicates the maximum number of contiguous paging messages that the mobile unit can skip without compromising on the MT-call performance.
ACTUAL_SKIP_FACTOR: This parameter indicates the actual number of contiguous paging messages that the mobile unit would skip, to save battery. The value of this factor should be within the range {0, MAX_PAGE_SKIP_ATTEMPT}.
DIV: Mathematical division of two operands. The result is shown in an integer format, omitting the fractional part.

Documents:

315-CHE-2006 AMENDED PAGES OF SPECIFICATION 24-10-2011.pdf

315-CHE-2006 AMENDED CLAIMS 29-12-2011.pdf

315-CHE-2006 AMENDED CLAIMS 24-10-2011.pdf

315-CHE-2006 AMENDED PAGES OF SPECIFICATION 29-12-2011.pdf

315-CHE-2006 AMENDED PAGES OF SPECIFICATION 15-02-2012.pdf

315-CHE-2006 CORRESPONDENCE OTHERS 29-12-2011.pdf

315-CHE-2006 EXAMINATION REPORT REPLY RECEIVED 24-10-2011.pdf

315-CHE-2006 FORM-1 15-02-2012.pdf

315-CHE-2006 FORM-13 29-12-2011.pdf

315-CHE-2006 FORM-3 29-12-2011.pdf

315-CHE-2006 FORM-3 24-10-2011.pdf

315-CHE-2006 OTHER PATENT DOCUMENT 24-10-2011.pdf

315-CHE-2006 POWER OF ATTORNEY 15-02-2012.pdf

315-CHE-2006 AMENDED CLAIMS 15-02-2012.pdf

315-CHE-2006 CORRESPONDENCE OTHERS 15-02-2012.pdf

315-CHE-2006 CORRESPONDENCE OTHERS.pdf

315-CHE-2006 CORRESPONDENCE PO.pdf

315-CHE-2006 FORM-18.pdf

315-CHE-2006 FORM-9.pdf

315-che-2006-abstract.pdf

315-che-2006-claim.pdf

315-che-2006-correspondence-others.pdf

315-che-2006-description(complete).pdf

315-che-2006-drawings.pdf

315-che-2006-form1.pdf

315-che-2006-form26.pdf


Patent Number 251206
Indian Patent Application Number 315/CHE/2006
PG Journal Number 09/2012
Publication Date 02-Mar-2012
Grant Date 01-Mar-2012
Date of Filing 24-Feb-2006
Name of Patentee SAMSUNG INDIA SOFTWARE OPERATIONS PRIVATE LIMITED
Applicant Address BAGMANE LAKEVIEW, BLOCK 'B', NO.66/1, BAGMANE TECH PARK, CV RAMAN NAGAR, BYRASANDRA, BANGALORE -
Inventors:
# Inventor's Name Inventor's Address
1 SANDIP HOMCHAUDHURI BAGMANE LAKEVIEW, BLOCK 'B', NO. 66/1, BAGMANE TECH PARK CV RAMAN NAGAR, BYRASANDRA BANGALORE - 650093 KARNATAKA INDIA
PCT International Classification Number H 04 B 1/40
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA