Digital radio paging communication system

• US 4,403,212 A
• Filed: 10/06/1980
• Issued: 09/06/1983
• Est. Priority Date: 10/09/1979
• Status: Expired due to Term

• Current Assignee: Nippon Electric Company Limited (NEC Corporation)
• Original Assignee: Nippon Electric Company Limited (NEC Corporation)
• Inventors: Masaki, Masaru
• Primary Examiner(s): Caldwell, Sr., John W.
• Assistant Examiner(s): Crosland, Donnie L.
• Application Number:
  US06/194,262
• Time in Patent Office: 1,065 Days
• Field of Search: 340/825.44, 340/825.48, 340/825.36, 340/825.37, 340/825.47, 340/311.1, 340/825.45, 340/825.46, 340/825.5, 340/825.51, 455/31-38, 179/2 EC
• US Class Current: 340/7.51
• CPC Class Codes: G08B 5/224 Paging receivers with visible signalling details

Abstract

A paging communication receiver receives carrier waves modulated by a sequence of signals comprising a calling signal, a display information signal and a discriminating signal. The modulated carrier wave is demodulated to retrieve the calling signal, display information signal and discriminating signal. The calling signal is detected and decoded to provide a detection signal, when the discriminating signal represents a calling signal. The detection signal causes a decoding for displaying information when the discriminating signal is the one representing the display information signal.

Claims

1. A paging communication receiver comprising first means for receiving a carrier wave modulated with a sequence of signals comprising a calling signal, a display information signal, and a discriminating signal immediately preceding each of said calling signal and display information signal;

second means for demodulating the modulated carrier wave into said sequence of signals;

third means for detecting said sequence of signals as said calling signal to provide a detection signal, when said discriminating signal identifies said calling signal;

fourth means responsive to said detection signal for decoding said sequence of signals as said display information signal to provide a decoded signal, when said discriminating signal identifies said display information signal; and

fifth means for displaying said decoded signal.

2. The receiver of claim 1 further comprising means responsive to said discriminating signal for separating said calling and display information signals.

3. The receiver of claim 1 or claim 2 wherein said receiver is one of a plurality of receivers used in a paging system, and said third means comprises means in each receiver for storing a signal which identifies that receiver, and means for comparing said stored signal with said calling signal in order to provide said detection signal.

4. The receiver of claim 3 and means for intermittently powering at least part of said receiver during stand-by periods for conserving energy of said power means.

5. The receiver of claim 3 and means for sounding an alert signal responsive to said comparing means providing said detection signal.

6. The receiver of claim 5 and means for sounding an alert signal in the form of a predetermined melody.

7. The receiver of claim 3 and means for checking the parity of signals demodulated from said carrier wave.

8. A method of paging a selected one from among a plurality of subscribers in a radio paging system comprising the steps of:

(a) detecting a broadcast carrier wave modulated by a plurality of binary encoded word signals of indeterminant length, each of said word signals being separated from other word signals by a plurality of discriminatory signals;

(b) demodulating said carrier wave to recover said encoded word signals;

(c) separating said encoded word signals into calling signals and display information signals in response to said discriminatory signal, whereby said system is adapted to use said indeterminant length word signals;

(d) detecting one of said separated calling signals; and

(e) displaying at least one of the separated display information signals and sounding an alarm at said particular receiver in response to a detected call for that receiver.

9. The method of claim 8 and the added step of intermittently powering equipment when said particular receiver is waiting for said broadcast carrier wave.