US4563680A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digital radio paging receiver
Assignee: NEC Corp
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Filing: 1983-01-25
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Granted: 1986-01-07
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Expires: 2003-01-25
Abstract
Abstract A multi-address radio paging receiver having a plug-in PROM which stores only one of the receiver's address codes, the remaining address codes of the receiver being generated by an exclusive OR operation on ROM stored codes and the one PROM stored code. The PROM stored address code and the exclusive OR generated address codes are compared to a received calling signal. If a match exists an alert signal, peculiar to the particular address code detected, is generated. The address codes are BCH codes. All address codes for a receiver can thus be altered by reprogramming the PROM to store a different signal address code.
Inventors
- 👤 Takeshi Nakajima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:16
CPC Classifications
H; H04; H04W; H04W88/00; H04W88/02; H04W88/022; H04W88/025; H04W88/026; Y; Y02; Y02D; Y02D30/00; Y02D30/70
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
221 words
A multi-address digital radio paging receiver of the type adapted to detect the presence of multi-address codewords in a selective calling signal, said receiver comprising: means for receiving said selective calling signal; first memory circuit means for storing a first address codeword assigned to said receiver and comprised of a BCH code and providing the content thereof in response to the received selective calling signal, said BCH code constituting one of said multi-address codewords detectable by said receiver; second memory circuit means for storing a plurality of codewords and providing the content thereof in response to the received selective calling signal, each of said plurality of codewords comprising a BCH code whose information contents differ from said first address codeword by such content that exclusive OR operation on said first address codeword and each of said plurality of stored codewords results in the other of said multi-address codewords; code generating means responsive to said received selective calling signal for performing said exclusive OR operation to provide the other of said multi-address codewords; and means for comparing said received selective calling signal with said first codeword and the other of said multi-address codewords, respectively, to provide, if they are identical with each other, an identity signal and to thereby detect the presence of said multi-address codewords in said received selective calling signal.
Claim 2
Dependent Claim
221 words
A multi-address digital radio paging receiver of the type adapted to detect the presence of multi-address codewords in a selective calling signal, said receiver comprising: means for receiving said selective calling signal; first memory circuit means for storing a first address codeword assigned to said receiver and comprised of a BCH code and providing the content thereof in response to the received selective calling signal, said BCH code constituting one of said multi-address codewords detectable by said receiver; second memory circuit means for storing a plurality of codewords and providing the content thereof in response to the received selective calling signal, each of said plurality of codewords comprising a BCH code whose information contents differ from said first address codeword by such content that exclusive OR operation on said first address codeword and each of said plurality of stored codewords results in the other of said multi-address codewords; code generating means responsive to said received selective calling signal for performing said exclusive OR operation to provide the other of said multi-address codewords; and means for comparing said received selective calling signal with said first codeword and the other of said multi-address codewords, respectively, to provide, if they are identical with each other, an identity signal and to thereby detect the presence of said multi-address codewords in said received selective calling signal.
Claim 3
Dependent Claim
40 words
A digital radio paging receiver, as claimed in claim 1, further comprising means for generating, in response to the output of said comparing means, different alert tones each corresponding to a different one of said first and second address codewords.
Claim 4
Dependent Claim
38 words
A digital radio receiver, as claimed in claim 2, wherein said receiving means comprises means for demodulating a carrier wave FSK-modulated with a modulating selective calling signal and supplying the demodulated output, as said received selective calling signal.
Claim 5
Dependent Claim
21 words
A digital radio paging receiver, as claimed in claim 1, wherein said first memory circuit means comprises a programmable read-only memory.
Claim 6
Dependent Claim
19 words
A digital radio paging receiver, as claimed in claim 4, wherein said second memory circuit means comprises read-only memories.
Claim 7
Dependent Claim
132 words
A digital radio paging receiver, as claimed in claim 1, wherein said selective calling signal includes at least a synchronizing codeword (SC) signal and a plurality of address codewords, and wherein said receiver further has an SC signal detecting means for detecting said synchronizing codeword signal in said received selective calling signal; SC detect pulser means for waveform-shaping the output of said SC signal detecting means; and read pulse generating means for generating in synchronization with the output of said SC detect pulser means, address signals, timing pulses and read-out pulses, said address signals reading out the contents of said first and second memory circuit means, said timing pulses synchronizing said code generating means with said selective calling signal, said read-out pulses reading out of said identity detecting means said identity signal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-01-06 | 1989-07-08 | 1990-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-06 | 1993-07-08 | 1994-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-06 | 1997-07-08 | 1998-01-07 | $7700.00 | Window Closed / Lapsed |