Title of Invention

A PROCESS FOR ESTABLISHING SIMULTANEOUS CONNECTIONS IN MAINTENANCE OF STANDARD INFORMATION TRANSMISSION RATE OVER A RADIO INTERFACE OF A MOBILE COMMUNICATION SYSTEM

Abstract

The process comprises the step of configurating a mobile communication system to a time multiplex process (for example TDMA) for multiple connections between mobile stations (MS1. MS2, MSk) and base stations (BS1,BS2) wherein informations (ni,si) for an existing connection between a mobile station (MS1) and a base station (BS1) are transmitted in time slots (ts1..ts8) of returning time frames (FR1,FR2). The number of time slots (for example ts1) in at least two time frames (FR1,FR2) which are used for the information of existing connections between the mobile station (MS1) and the base station (BS1) is compressed and the transmission rate is increased for the informations contained in remaining time slot. The free time slots arising through compression are utilised for transmission of information (ni,si) of a further connection independent from existing connections.

Full Text

-1A- Description. establishing simultaneous ccnnections in maintenance of standard The invention refers to a process for/information trans- mission rate over a radio interface of a mobile- communication system as also a mobile station and a base station for carrying out the process. The design of digital radio communication system is shown in J.Oudelaar, "Evolution towards UMTS", PIMRC 94, 5th IEEE International Symp. on personal, Indoor and Mobile communications. The Hague, NL, 18-22 September 1994, P.852- 856 and M.Lenti, H.Hage-man, "Paging in UMTS", Race Mobile Tele communications workshop, Vol.1, Amsterdam, NL, 17-19 May 1994 P 405- 410. The present existing mobile radio system GSM (Global System for Mobile Communication) is a radio communications- system with a TDMA - component for participant separation (time division multiple access). As per a frame structure informations of participant connections between mobile stations and base stations are transmitted in time slots. The transmission takes place blockwise. From the publication script DE 4210 305 A1 a process for data transmission with variable volume of traffic is known, in which a definite period of time of a data flow is distributed in parts, whose number depends on the volume of traffic. The different parts therein are coded with more or less many codes orthogonal to each other so that a mixed TDMA/CDMA- System (CDMA, code division multiple access) arises. The assignment lies at the base of the invention, to prepare a process and device which makes possible in a mobile-communication system the design of simultaneous connections in maintenance of standard information transmission rate. This assignment is solved through the process with the features of Patent claim 1, the mobile station with features of patent claim 15 and the base station with the features of patent claim 16. Further developments of invention are to be taken from sub claims. A mobile communication system plans a time multiplex process for multiple connections between mobile stations and base stations, wherein informations for an existing connention -2- between a mobile station and a base station are transmitted in time slots of returning time frame. As per invention, the number of time slots in at least two time frames, which are used for the information of existing connections between mobile station and base station are compressed and the transmission rate for the information contained in the remaining time slots is increased. The free time slots arising through compression utilized for transmission of informations of at least one further connection independent from the existing connection. Through the compression of time slot for information transmission of already existing connection, the mobile station can build up at the same time one or more, further independent connection in the time slot made free. This enables the mobile station- independent of any volume of traffic- to utilise multiple simultaneous connections to one or also different base stations. Through the increase of information transmission rate in the remaining time slots for the first connection the standard information transmission rate of total information flow- for example in a multiframe with multiple time frame-can be maintained. Additional effect of advantage is the better utilization of radio technical resources through at least one parallel connection to come there without the band width required to be increased. Advantageous application of invention exist for the mobile station therein to utilise at the same time separate connections independent from each other for multi media or multiple services, for example data and speech services. Particularly advantageously, the invention is effective for an interruption free further connection, of an existing combination (handover) since, to begin with the second connection to a target - base station can be built and the sufficient quality of this connection can be checked as also the required synchronisation can be carried out before followingly - depending on the found out quality of new connection - the interruption free handover takes place and the so far connection is released. -3- An advantageous application of invention exists for the mobile station also therein to utilize the compression of time slots for neighbour cell measurements for the identification of neighbouring base stations. Search mechanism has proved specially favourable then if the mobile-communication system in a TDD- Modus (time division duplex) is operated, in which the base stations and mobile stations alternately transmit on one-and the same high frequency channel. Since the neighbouring base stations do not transmit constantly, the neighbouring cell measurement in the TDD-operation type first can be really carried out through the compression of time slots in an extended time window of at least two time frames. It is of advantage as per further development of invention, that the transmission of information of existing connection is released at regular intervals in respective time slots of sequential time frame of a multiframe and is replaced through the information transmission for the further connection. It has proved favourable, since it is specially simple to control, to release the transmission of information of existing connection in time slot at least of each second time frame of a multiframe and to replace through information transmission for further connection. According to another further development of invention the transmission of information of existing connection can also be released at irregular intervals in respective time slots of sequential time frame of a multiframe and replaced through the information transmission for further connection. Preferably a number of codes for connection of mobile station to base station are allocated in time slots and is increased in the compre ssion of time slot for raising the information transmission rate. This is a specially advantageous procedure, which particularly in coining of mobile communication system as TDMA/CDMA radio communica tion system does not signify control technically any additional ex pense. A communication system of this type shows frequency channels built through time slots, in which at the same time information of multiple connections between mobile station and base stations are transmitted wherein informations of different connections are differ- entiable as per a fine structure individual to connection, A mobile station for carrying out of process as per invention shows a signal processing device for building of a -4- further, connection independent from the existing connection and a control set up for selection of free time slots arising through the compression for the transmission of informations of independent connections. A base station for carrying out of process as per invention covers a control set up for compression of number of time slots in at least two returnable time frames, which are used for the informations of existing connections between the mobile station and the base station and for increase of transmission rate for the informations contained in the remaining time slots. Further of this, a transmission equipment for transmitting out of signaling information to the mobile station is planned, with help of which the mobile station identifies the free time slots arising through the compression. Followingly, the invention is illustrated closer with help of an execution example with reference to the accompanying diagramatic representations. They show therein, Fig. 1: A schematic diagram of a mobile communication system. Fig. 2: A schematic representation of frame structure for information transmission. Fig. 3: Schematic diagram of a base station and a mobile station. The mobile communication system represented in Figure 1 corresponds in its structure a known GSM - system which shows a multiple of mobile exchange location MSC, which are interconnected to each other or rather generate the entry to a hard net PSTN. These mobile exchange locations HSC are connected at least with one base station control BSC. Each base station control BSC makes possible again a connection to at least one base station, in present example to two base stations BS1 and BS2. Such a base station BS1, BS2 is a radio station which is arranged for coverage of a radio area, in order to build, dismantle and maintain a news connection from/to mobile station MS in the radio area over a radio interface. In Figure 1 for example multiple connections for -5- transmission of utility information ni and signaling information information al between mobile stations MS1, MS2 and base station BS1 as also between a mobile station MSK and the base station BS2 are represented. An operation - and service centre OMC realises control - and service functions for the mobile communication systems or rather for parts there from. The functioning of this structure is transferable on other radio communications systems in which the invention can come to application. The mobile - communication system plans a tine multiplex process for the connections between the mobile station MS1, MS2 and MSK and base stations BS1 and BS2. Therein for example a tine slot ts1 in returning time frame FR1, FR2••• for transmission of information ni, si for an existing connection between the mobile station MS1 and the base station BS1 as also for example a time slot ts2 in returning time frame FR1, PR2 for transmission of informations ni, si for an existing connection between the mobile station MS2 and the base station BS1 are reserved. As per invention the number of time slots ts1 or rather ts2 in the time frame FR1...., which are used for the information of existing connection between the mobile station MS1 or rather MS2 and the base station BS1, are compressed such, that the free time slots ts1 or rather ts2 arising through the compression for transmission of informations of a further connection independent from the existing connections are utilized. In order to maintain the information transmission rate as standard the transmission rate for the information contained in the remaining time slots ts1 or rather ts2 is increased. For the present example it means, that from the time slots ts1 of first and second time frame FR1 and FR2 alloted for the existing connection, the time slot ts1 of first time frame FR1 is used as ever for information transmission to the existing connection, the time slot ts1 of second time frame FR2 however is used for transmission of information ni, si of second connection from the mobile station MS1. The second connection, can then be -6- built up either for up till now base station BS1 . for example for the simultaneous utilisation of multiple services like data and speech transmission or to another base station SS2 for example as target - base 3tation in further connection of existing combination (Handover). In case of handover, it takes place uninterrupted, since for the independent second connection built from the existing connection first the quality can be tested out before a hand over is carried out. Through the increase of information rate in remaining time slot ts1 of time frame FR1, for the mobile station MS1 no information on the existing first connection for base station BS1 gets. lost. An increase of transmission rate is advantageously through allocating of code in the tine slot ts1••• of time frame is reached, which makes possible as transmission of information of parallel connection corresponding to the number of code per time slot. Build up and content of time frame for information transmission is visible from Figure 2. As per TDMA - components a distribution of wide banded frequency range B = 1.6 MHz is planned in multiple time slots te, for example eight time slots ts1... ts8, for each time frame FR1, FR2 (TDMA - frames). Each time slot ts builds within frequency range B a frequency channel. With in the frequency channels of time slots ts1....ts8 under building, usable or signalling informations of multiple connections are transmitted in radio blocks. These radio blocks for useful data transmission are made out of sections with data D, in which sections with reception side wise known training sequences tseq1 tseqk axe embedded. The data d are spreaded with a fine structure,a participant code C individual to connection so that reception sidewise for example k connections are separable through this CDMA - component. The spread of individual symbol of data d causes that within the symbol duration Tsymq chips of duration T chip are transmitted. -7- The Q chips build therein the participant code C individual to connection. Further the time slots ts1 ....ts8 show a protection time gp for compensation of different signal opening time of connections. Within a wide banded frequency range B the sequential time slots ts are classified as per a frame structure. Thus for example eight time slots ts1 ...ts8 are always united to a frame FR1,FR2 and the returning frames FR1,FR2 are united to a multi-frame. In selected example as per Fig.1 the time slot ts1 builds in the frames FR1,FR2... a frequency channel for transmission of information from/to the mobile station MS1 and the time slot ts2 builds in the frames FR1,FR2... a frequency channel for transmission of information from/to the mobile station MS2. The participant signals of mobile station MS1 are differentiated through the codes C1, C2... in time slot ts1 as also the participant signals of mobile station MS2 through the codes C1.. in time slot ts2 as per the CDMA - component. In deviation from the known procedure, the number of time slots ts1 in the sequential time frame FR1,FR2... which are used for the information transmission from/to of mobile station MS1 on the existing connection are eompressed.If this is applied for example on each second time frame FR<.... in multiframes the time slots ts1 made free respective frame can be utilised for at least one further connection dependent from first connection. participant signals of mobile station ms1 spreaded slot fr2 with codes c1 and c2 are transmitted fr1 there example provided c3 c4- order to differentiate them certainty already contained signal. through that information transmission rate increases compressed present each third fifth frames. arising compression second fourth sixth frames place up now informations other useful or signaling> -8- information of other connections, which the mobile station MS1 utilises simultaneously, are entered. Same is valid for other mobile stations, also if in Fig.2 only in example of connections from/to of mobile station MS1 the procedure as per invention is described. The transmission of information of existing connection generally at regular intervals - for example in each second time frame - of time slot can be released in sequential time frame of a multiframe and can be replaced through the information transformation for further connections. Also the transmission of information of existing connection at irregular interval is basically possible. With the help of Figure 3 the structure of a frequency channel RACH for a chance intervention is shown. The wide banded frequency range B for example with B= 1.6 MHZ, which for example from the frequency band of an organisation channel of mobile radio net admit with duplex interval calculated, contains four sub areas OB with for example 200 KHZ band width, which are separated through a range of 200 KHZ, in order to reduce reciprocal trouble. Within this sub area UB, on requirement access radio blocks can be transmitted from the mobile station MS without previous linewise allocation and without spreading. Thus GSM random access radio blocks can be used. An advantageous application of invention exists for the mobile station also therein, to utilise the compression of time slots for neighbouring cell measurement for identification of neighbouring base stations. The search mechanism has proved as specially favourable when the mobile communication system is operated in a TDD- Modus (time division duplex) in which the base station and the mobile stations alternately transmit on one- and the same high frequency channel. Since the neighbouring base stations do not transmit constantly, the neighbouring cell measurement in the TDD- operation type can be carried out actually first through the compression of time slots in an extended -9- time window of at least two time frames. Figure 3 shows in an example the radio transmission in upward direction from mobile station MS1, MS2 to a single base station BS1. The signal gets to the receiving base station BS1 after a transmission over the frequency channels. Thus the participant signals of mobile station MB1 in time slot ts1 of time frame FR1 over the already existing first connection and other participant signals of mobile station MS1 in time slot ts1 of time frame FR2 over the independent second connection are transmitted to base station BS1. Further the participant signals of mobile station MS2 which are contained in time slot ts2 of time frame FR1 and of time frame FR2 arrive. The base station BS1 evaluates the receiving signal, separates the participant signal in the frequency channels as per the different connections and detects the informations for utility information and signaling informat ions. The base station contains for this purpose a transmission/receiving equipment SE/EE, which strengthens the receiving signal, converts in the base band and demodules. In an analogous /digital converter, the receiving signals are converted in symbols with discreet value stocks, for example digitalled. She radio blocks transmitted as per the TDMA/CDMA components are evaluated by a signal evaluation equipment SA which for example as signalling processor contains a JD- processor for detection of utility informations and signalling informations as per JD process (Joint detection). A control equipment BE causes, that the number of time slots - for example ts1 - in the repeatedly transmitted time frames FR1, FR2... which are utilised for information transmission on the existing connections is compressed and the transmission rate for the information contained in the remaining time slot is increased. First it receives from mobile station MS1 a signalling information which signals the desire of mobile station MS1 for building of a further connection for another application and reacts in the above wey. The transmission equipment SE/EE transmits back a signaling information to the -10- mobile station MS1 in which the free time slot of mobile station MS arising through compression is communicated. The mobile station contains a sendee field T, a signal processing equipment SP, a control equipment ST and a transmitting /receiving equipment SE/EE At service field T, the participant can make the inputs among others an input for the desire of building connection during the existing connection. In the signal processing equipment SP, the building of at least a further connection independent from existing connections is initiated, as soon as the control equipment SE has selected the time slot/slots out of possible time slots transmitted from the base stations# 11 WE CLAIM 1. Method for information transmission via radio interface in a mobile communications system which uses a time-division multiplexing method (for example TDMA) for a number of connections between mobile stations (MS1, MS2, MSK) and base stations (BS1, BS2) and, in the process, in each case transmits information items (ni, si) for an existing connection between a mobile station (MS1) and a base station (BS1) in timeslots (ts1 ...ts8) in recurring time frames (FR1, FR2), characterized in that the number of timeslots (for example ts1) which are used in at least two time frames (FR1, FR2) for transmitting the information items (ni, si) for a connection which exists between a mobile station ( MS1 ) and a base station ( BS1 ) is reduced, and the transmission rate for the information items contained in the remaining timeslots ( for example ts 1/FR2 ) is increased, and in that the free timeslots (for example ts 1/FR2) which result from the reduction are used for simultaneous transmission of information items (ni, si) for at least one parallel connection, which is independent of the existing connection, between the same mobile station (MS1) and a base station (BS1, BS2). 2. Method as claimed in claim 1, wherein the transmission of the information items ( ni, si) for the existing connection at regular intervals in the respective timeslot ( ts1 ) of successive time frames ( FR1, FR2 ) in a superframe is stopped, and is replaced by the information transmission for the further connection. 3. Method as claimed in claim 1 or 2, wherein the transmission of the information items ( ni, si) for the existing connection in the timeslot (ts1) of at least every alternate timeframe ( FR2 ) in a superframe is stopped, and is replaced by the information transmission for the further connection. 2. 12 4. Method as claimed in claim 1, wherein the transmission of the information items (ni, si) for the existing connection at irregular intervals in the respective timeslot (ts1) of successive timeframes (FR1, FR2) in a superframe is stopped, and is replaced by the information transmission for the further connection, 5. Method as claimed in one of the preceding claims, in which a number of codes (for example c1 to c2) for connections from the mobile station ( MS1) to the base station (BS1) in the timeslot (ts1) are given away, and the number of timeslots (for example ts1) in the reduction is increased in order to increase the information transmission rate. 6. Method as claimed in one of the preceding claims, wherein the mobile communications system is in the form of a TDMA/CDMA radio communications system with frequency channels which are formed by timeslots (ts1...ts8) in which information items (ni, si) for a number of connections are transmitted simultaneously between the mobile station (MS1) and the base station ( BS1 }, with the information items (ni, si) for different connections being distinguishable on the basis of a connection-specific fine structure. 7. Method as claimed in one of the preceding claims, wherein the reduction in the number of timeslots (ts1) from the mobile station (MS1) is used for setting up at least one simultaneous connection to the same base station (BS1) or to one more other base stations (BS2). 8. Method as claimed in claim 7, wherein the parallel connections from the mobile station (MS1) are used for information transmission for a number of services or applications in parallel. 9. Method as claimed in claim 8, wherein the parallel connections from the mobile station (MS1) are used for information transmission for a voice service and a data service in parallel. 9. 13 10.Method as claimed in one of the preceding claims, wherein the compression of the timeslots (ts1) from the mobile station (MS1) is used for setting up a simultaneous connection to a destination base station (BS2) to which the existing connection is intended to be passed on. 11.Method as claimed in claim 10 wherein the synchronization of the simultaneous connection to the destination base station (BS2) is carried out, and its quality is checked, before switching on to the new connection, and before clearing the previously existing connection, 12.Method as claimed in one of the preceding claims, wherein the reduction in the number of timeslots (ts1) from the mobile station (MS1) is used for setting up a simultaneous connection to the same base station (BS1) or to one or more other base stations (BS2). 13.Method as claimed in one of the preceding claims, wherein the reduction in the number of timeslots (ts1) from the mobile station (MS1) is used for adjacent cell measurement in order to identify adjacent base stations (BS2). 14.Method as claimed in claim 13, wherein the mobile communications system is operated using a TDD mode, in which the base stations (BS1, BS2) and the mobile stations (MS1, MS2, MSK) transmit alternately on one and the same radio-frequency channel. 15.A device for carrying out the process as claimed in claims 1 to 14, comprising a mobile station having a signal processing equipment (SP) for building of at least one further connection independent of existing connections, a control equipment (SE) for selection of free time slots (ts1) arising through compression including the transmission of information of independent connection; a base station provided with a control equipment (BE) for compression of a plurality of time slots (ts1) in at least two time (FR1, FR2), the time slots (ts1) being used for the information of existing connection between the mobile station (MS1) and the base station (BS1), said control equipment (BE) increasing 14 transmission rate for the informations contained in the remaining time slots (ts1), and a transmission equipment (SE/EE) being arranged therein for transmitting out of signaling information (si) to te mobile station (MS1), characterized in that said signal processing equipment (SP) initiates building of at least a further connection independent of existing connections immediately on selection of the time slot/slots by said control equipment (SE) out of a plurality of time slots transmitted from said base stations (BS1). Dated this 2nd day of September, 1998 The process comprises the step of configurating a mobile communication system to a time multiplex process (for example TDMA) for multiple connections between mobile stations (MS1. MS2, MSk) and base stations (BS1,BS2) wherein informations (ni,si) for an existing connection between a mobile station (MS1) and a base station (BS1) are transmitted in time slots (ts1..ts8) of returning time frames (FR1,FR2). The number of time slots (for example ts1) in at least two time frames (FR1,FR2) which are used for the information of existing connections between the mobile station (MS1) and the base station (BS1) is compressed and the transmission rate is increased for the informations contained in remaining time slot. The free time slots arising through compression are utilised for transmission of information (ni,si) of a further connection independent from existing connections.

Documents:

01580-cal-1998-abstract.pdf

01580-cal-1998-claims.pdf

01580-cal-1998-correspondence.pdf

01580-cal-1998-description(complete).pdf

01580-cal-1998-drawings.pdf

01580-cal-1998-form-1.pdf

01580-cal-1998-form-2.pdf

01580-cal-1998-form-3.pdf

01580-cal-1998-form-5.pdf

01580-cal-1998-g.p.a.pdf

01580-cal-1998-priority document others.pdf

01580-cal-1998-priority document.pdf

1580-CAL-1998-(09-10-2012)-FORM-27.pdf

1580-CAL-1998-CORRESPONDENCE 1.1.pdf

1580-CAL-1998-CORRESPONDENCE 1.2.pdf

1580-CAL-1998-CORRESPONDENCE.pdf

1580-CAL-1998-FORM-27.pdf

1580-cal-1998-granted-abstract.pdf

1580-cal-1998-granted-claims.pdf

1580-cal-1998-granted-correspondence.pdf

1580-cal-1998-granted-description (complete).pdf

1580-cal-1998-granted-drawings.pdf

1580-cal-1998-granted-examination report.pdf

1580-cal-1998-granted-form 1.pdf

1580-cal-1998-granted-form 2.pdf

1580-cal-1998-granted-form 5.pdf

1580-cal-1998-granted-gpa.pdf

1580-cal-1998-granted-letter patent.pdf

1580-cal-1998-granted-others.pdf

1580-cal-1998-granted-priority document.pdf

1580-cal-1998-granted-reply to examination report.pdf

1580-cal-1998-granted-specification.pdf

1580-cal-1998-granted-translated copy of priority document.pdf

1580-CAL-1998-PA 1.1.pdf

1580-CAL-1998-PA.pdf