Title of Invention

A COMMUNICATION SYSTEM FOR IMPROVING PAGING COVERAGE

Abstract

A communication system for improving paging coverage and for extending paging coverage by interfaclllg with the existing public paging system without the requirement of any additional control or interface signal) comprising a receiving antenna for receiving the UHF signal; a UHF receiver for down converting the UHF signal and extracthlg the original pagll1g ll1fonnation and control signals from the said signal available in the form of audio tones; a VHF transmitter for receiving the audio tones and extracting the paging information (Bits Zero's and One's) and thereafter modulating and amplifying the same to generate a VHF signal; a transmitting antenna for transmitting the VHF signal; and a power supply unit. (Fig. I)

Full Text

This invention relates to a communication system for improving paging coverage in remote areas of a city. 1 .Introduction: Communication Systems are classified as Wireless or Wireline systems. A wireless system uses radio wave propagation to provide communication facilities while a wireline system uses copper or optical fiber to provide communication facilities. Paging provides simple, one way communication using wireless technology. It operates in the Ultra High Frequency -UHF or very High Frequency _VHF bands. A pager is a small, portable device which is carried by the user. Pager enables the user to receive and read messages. A Pager basically consists of a receiver, demodulator, decoder, Liquid Control Display-LCD and memory. 2.Types of Paging System: Paging systems may be classified as In -house or Public Paging Systems. a) In House Paging System: These systems also known as COPS-Customer Owned Paging System or Private Paging System and are used to provide paging within a limited area - like within a factory, hospital, hotel. These are stand alone systems-they cannot be used to receive messages over large areas, like in a city. The coverage or page reception is limited to 1-2 KMs, Capacity varies from 10 to 200 customers. System configuration is; i) Encoder: Accepts messages and encodes them ii) Transmitter: Encoded messages are modulated, amplified, & transmitted. Output Power 1-5 watts. The system is normally used for internal paging. If the system has to process calls from callers external to the system, additional resources like telephone lines, Exchange etc. are required. The system will still be available to handle few selected callers only and is not capable for handling huge volumes of Paging requests. b)Public or Wide Area paging System: These are used to provide paging over a wide area , like in a city. The pagers can be used almost anywhere in the city and the paging system is interfaced to the Telephone Exchange (PSTN interface) in the city. This interface makes it possible to access the paging center for sending messages from within the city. Messages can also be sent from anywhere within the country or other countries. The user receives messages on his pager almost anywhere in the city. The communication system, according to this invention, for improving paging coverage in remote areas in a city and for extending paging coverage in hospitals, underground structures, industrial plants and the like, by interfacing with the existing public paging system , without the requirement of any additional control or interface signal, comprises a receiving antenna for receiving the UHF signal; a UHF receiver for down converting the UHF signal and extracting the original paging information and control signals from the said signal available in the form of audio tones; a VHF Transmitter for receiving the audio tones and extracting the paging information (Bits Zero's and One's) and thereafter modulating and amplifying the same to generate a VHF signal; a Transmitting Antenna for transmitting the VHF signal; and a power supply unit. This invention will now be described in farther detail by referring to the accompanying drawings wherein Fig. 1 illustrates a radio paging system Fig. 2 illustrates a block diagram of a paging system and Fig . 3. illustrates , by way of example, a block diagram of an embodiment of this invention. A simple description of a paging system is given in Appendix I hereto, the specifications of the UHF Receiver and VHF Receiver are given in Appendix II hereto and the test results of the communication system proposed herein are given in Appendix IV hereto. We claim: 1. A communication system for improving paging coverage and for extending paging coverage by interfacing with the existing public paging system, without the requirement of any additional control or interface signal, comprising a Receiving Antenna for Receiving the UHF signal; a UHF receiver for down converting the UHF signal and extracting the original paging information and control signals from the said signal available in the form of audio tones a VHF transmitter for receiving the audio tones and extracting the paging information (Bits Zero 's and One's) and thereafter modulating and amplifying the same to generate a VHF signal ; a transmitting antenna for transmitting the VHF signal; and a power supply unit 2. A communication system as claimed in Claim 1 wherein the VHF Transmitter incorporates an AFSK Demodulator for extracting the paging information from the audio tones. 3. A communication system as claimed in Claim 1 or Claim 2 wherein the Receiving Antenna is Yagi Antenna provided with a coaxial cable. 4. A communication system as claimed in any one of the preceding claims wherein the Transmitting Antenna is an Omni or Yagi Antenna.

Documents:

1713-mas-1998-abstract.pdf

1713-mas-1998-claims duplicate.pdf

1713-mas-1998-claims original.pdf

1713-mas-1998-correspondence others.pdf

1713-mas-1998-correspondence po.pdf

1713-mas-1998-description complete duplicate.pdf

1713-mas-1998-description complete original.pdf

1713-mas-1998-description provisinol.pdf

1713-mas-1998-drawings.pdf

1713-mas-1998-form 1.pdf

1713-mas-1998-form 19.pdf

1713-mas-1998-form 26.pdf

1713-mas-1998-form 5.pdf