US5444737A
Expired / Lapsed
US
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Wireless data transceiver
Assignee: National Semiconductor Corp
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Filing: 1993-11-10
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Granted: 1995-08-22
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Expires: 2013-11-10
Abstract
Abstract A full duplex data transceiver for transmitting and receiving trinary frequency-modulated ("FM") signals representing binary data includes at least one antenna and a single oscillator which serves as both the radio frequency ("RF") signal source for the transmitter and the local oscillator ("LO") signal source for the receiver. During signal transmission, the oscillator output is frequency-modulated to provide a FM transmit signal to the antenna. The oscillator output is frequency-modulated with binary transmit data by modulating an error feedback signal which serves as the control voltage for a voltage-controlled oscillator in a phase-lock-loop, thereby producing the FM transmit signal. During signal reception, the oscillator output, in the form of the transmitted FM signal, is attenuated and coupled into the receiver along with a FM receive signal from the antenna, or alternatively is received via a separate receive antenna along with the FM receive signal, for mixing therewith to down-convert the FM receive signal. As part of the demodulation of the down-converted FM receive signal, the binary transmit data is subtracted out. The FM transmit and receive signals are trinary (f -P , f C , f +P ) and represent encoded binary data. The center frequency f C corresponds to an absence of a binary data signal transition, the lower peak frequency f -P corresponds to a negative binary data signal transition and the upper peak frequency f +P corresponds to a positive binary data signal transition.
Inventors
- 👤 Peter K. Cripps
- 👤 Tomany Szilagyi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:27
CPC Classifications
H; H03; H03C; H03C3/00; H03C3/02; H03C3/09; H03C3/0908; H03C3/0975; H04; H04B; H04B1/00; H04B1/38; H04B1/40; H04L; H04L25/00; H04L25/38; H04L25/40; H04L25/49; H04L25/4917; H04L25/4923; H04L25/4925; H04L27/00; H04L27/10; H04L27/12; H04L27/14; H04L27/144; H04L27/148
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
250 words
A data transceiver for transmitting and receiving modulated radio frequency (RF) signals, comprising: an antenna for transmitting a first modulated RF signal and receiving a second modulated RF signal; signal coupler means coupled to said antenna for receiving and coupling thereto a first portion of said first modulated RF signal and for receiving and coupling therefrom said second modulated RF signal; transmitter means coupled to said signal coupler means for receiving a first modulation signal M1 and generating therefrom a second modulation signal M2, generating a RF signal having a first carrier frequency F1, modulating said RF signal in accordance with said first modulation signal M1, and providing said modulated RF signal to said signal coupler means as said first modulated RF signal; and receiver means coupled to said signal coupler means and said transmitter means for receiving via said signal coupler means said second modulated RF signal which includes a second carrier frequency F2 modulated by a third modulation signal M3, receiving further via said signal coupler means a second portion of said first modulated RF signal, and mixing said received second portion of said first modulated RF signal and said received second modulated RF signal to produce a modulated intermediate frequency (IF) signal having a modulated center frequency F3 equal to a difference |F1-F2| between said first carrier frequency F1 and said second carrier frequency F2, and further for receiving from said transmitter means said second modulation signal M2 and in accordance therewith demodulating said modulated IF signal.
Claim 2
Dependent Claim
250 words
A data transceiver for transmitting and receiving modulated radio frequency (RF) signals, comprising: an antenna for transmitting a first modulated RF signal and receiving a second modulated RF signal; signal coupler means coupled to said antenna for receiving and coupling thereto a first portion of said first modulated RF signal and for receiving and coupling therefrom said second modulated RF signal; transmitter means coupled to said signal coupler means for receiving a first modulation signal M1 and generating therefrom a second modulation signal M2, generating a RF signal having a first carrier frequency F1, modulating said RF signal in accordance with said first modulation signal M1, and providing said modulated RF signal to said signal coupler means as said first modulated RF signal; and receiver means coupled to said signal coupler means and said transmitter means for receiving via said signal coupler means said second modulated RF signal which includes a second carrier frequency F2 modulated by a third modulation signal M3, receiving further via said signal coupler means a second portion of said first modulated RF signal, and mixing said received second portion of said first modulated RF signal and said received second modulated RF signal to produce a modulated intermediate frequency (IF) signal having a modulated center frequency F3 equal to a difference |F1-F2| between said first carrier frequency F1 and said second carrier frequency F2, and further for receiving from said transmitter means said second modulation signal M2 and in accordance therewith demodulating said modulated IF signal.
Claim 3
Dependent Claim
16 words
A data transceiver as recited in claim 1, wherein said signal coupler means comprises an attenuator.
Claim 4
Dependent Claim
52 words
A data transceiver as recited in claim 1, wherein said signal coupler means comprises a directional coupler for receiving said first modulated RF signal, outputting said first portion of said first modulated RF signal to said antenna and coupling said second portion of said first modulated RF signal to said receiver means.
Claim 5
Dependent Claim
46 words
A data transceiver as recited in claim 1, wherein said transmitter means comprises a phase-lock-loop which includes a frequency-controllable oscillator, wherein a frequency error signal is generated and combined with said received first modulation signal M1 to produce a frequency control signal for said frequency-controllable oscillator.
Claim 6
Dependent Claim
18 words
A data transceiver as recited in claim 4, wherein said first modulated RF signal comprises a frequency-modulated signal.
Claim 7
Dependent Claim
19 words
A data transceiver as recited in claim 4, wherein said frequency control signal comprises said second modulation signal M2.
Claim 8
Dependent Claim
67 words
A data transceiver as recited in claim 1, wherein said receiver means comprises: an IF circuit for receiving and mixing said second portion of said first modulated RF signal and said second modulated RF signal to produce said modulated IF signal; and a demodulator connected to said IF circuit for receiving said second modulation signal M2 and in accordance therewith receiving and demodulating said modulated IF signal.
Claim 9
Dependent Claim
34 words
A data transceiver as recited in claim 7, wherein said IF circuit comprises a single-input mixer which receives said first and second modulated RF signals on a single signal line from said receiver antenna.
Claim 10
Dependent Claim
15 words
A data transceiver as recited in claim 7, wherein said demodulator comprises a frequency discriminator.
Claim 11
Dependent Claim
76 words
A data transceiver as recited in claim 1, wherein said receiver means comprises: an IF circuit for receiving and mixing said second portion of said first modulated RF signal and said second modulated RF signal to produce said modulated IF signal; and a demodulator connected to said IF circuit for receiving and demodulating said modulated IF signal to produce a baseband signal, and for receiving and subtracting said second modulation signal M2 from said baseband signal.
Claim 12
Dependent Claim
34 words
A data transceiver as recited in claim 10, wherein said IF circuit comprises a single-input mixer which receives said first and second modulated RF signals on a single signal line from said receiver antenna.
Claim 13
Dependent Claim
15 words
A data transceiver as recited in claim 10, wherein said demodulator comprises a frequency discriminator.
Claim 14
Dependent Claim
241 words
A data transceiver for transmitting and receiving modulated radio frequency (RF) signals, comprising: an antenna which transmits a first modulated RF signal and receives a second modulated RF signal; a signal coupler, connected to said antenna, which receives and couples thereto a first portion of said first modulated RF signal and receives and couples therefrom said second modulated RF signal; a modulator-transmitter, connected to said signal coupler, which receives a first modulation signal M1 and generates therefrom a second modulation signal M2, generates a RF signal having a first carrier frequency F1, modulates said RF signal in accordance with said first modulation signal M1, and provides said modulated RF signal to said signal coupler as said first modulated RF signal; and a demodulator-receiver, connected to said signal coupler and said modulator-transmitter, which receives via said signal coupler said second modulated RF signal including a second carrier frequency F2 modulated by a third modulation signal M3, receives further via said signal coupler a second portion of said first modulated RF signal, and mixes said received second portion of said first modulated RF signal and said received second modulated RF signal to produce a modulated intermediate frequency (IF) signal having a modulated center frequency F3 equal to a difference |F1-F2| between said first carrier frequency F1 and said second carrier frequency F2, and further which receives from said modulator-transmitter said second modulation signal M2 and in accordance therewith demodulates said modulated IF signal.
Claim 15
Dependent Claim
241 words
A data transceiver for transmitting and receiving modulated radio frequency (RF) signals, comprising: an antenna which transmits a first modulated RF signal and receives a second modulated RF signal; a signal coupler, connected to said antenna, which receives and couples thereto a first portion of said first modulated RF signal and receives and couples therefrom said second modulated RF signal; a modulator-transmitter, connected to said signal coupler, which receives a first modulation signal M1 and generates therefrom a second modulation signal M2, generates a RF signal having a first carrier frequency F1, modulates said RF signal in accordance with said first modulation signal M1, and provides said modulated RF signal to said signal coupler as said first modulated RF signal; and a demodulator-receiver, connected to said signal coupler and said modulator-transmitter, which receives via said signal coupler said second modulated RF signal including a second carrier frequency F2 modulated by a third modulation signal M3, receives further via said signal coupler a second portion of said first modulated RF signal, and mixes said received second portion of said first modulated RF signal and said received second modulated RF signal to produce a modulated intermediate frequency (IF) signal having a modulated center frequency F3 equal to a difference |F1-F2| between said first carrier frequency F1 and said second carrier frequency F2, and further which receives from said modulator-transmitter said second modulation signal M2 and in accordance therewith demodulates said modulated IF signal.
Claim 16
Dependent Claim
15 words
A data transceiver as recited in claim 13, wherein said signal coupler comprises an attenuator.
Claim 17
Dependent Claim
50 words
A data transceiver as recited in claim 13, wherein said signal coupler comprises a directional coupler which receives said first modulated RF signal, outputs said first portion of said first modulated RF signal to said antenna and couples said second portion of said first modulated RF signal to said demodulator-receiver.
Claim 18
Dependent Claim
45 words
A data transceiver as recited in claim 13, wherein said modulator-transmitter comprises a phase-lock-loop which includes a frequency-controllable oscillator, wherein a frequency error signal is generated and combined with said received first modulation signal M1 to produce a frequency control signal for said frequency-controllable oscillator.
Claim 19
Dependent Claim
18 words
A data transceiver as recited in claim 16, wherein said first modulated RF signal comprises a frequency-modulated signal.
Claim 20
Dependent Claim
19 words
A data transceiver as recited in claim 16, wherein said frequency control signal comprises said second modulation signal M2.
Claim 21
Dependent Claim
76 words
A data transceiver as recited in claim 13, wherein said demodulator-receiver comprises: an IF circuit which receives and mixes said second portion of said first modulated RF signal and said second modulated RF signal to produce said modulated IF signal; and a frequency demodulator, connected to said IF circuit, which receives and frequency-demodulates said modulated IF signal to produce a baseband signal, and which receives and subtracts said second modulation signal M2 from said baseband signal.
Claim 22
Dependent Claim
34 words
A data transceiver as recited in claim 19, wherein said IF circuit comprises a single-input mixer which receives said first and second modulated RF signals on a single signal line from said signal coupler.
Claim 23
Dependent Claim
166 words
A data transceiving method for transmitting and receiving modulated radio frequency (RF) signals, comprising the steps of: receiving a first modulation signal M1 and generating a second modulation signal M2 therefrom; generating a RF signal having a first carrier frequency F1; modulating said RF signal in accordance with said first modulation signal M1; transmitting said modulated RF signal as a first modulated RF signal via an antenna; receiving via said antenna a second modulated RF signal having a second carrier frequency F2 modulated by a third modulation signal M3; receiving via a signal coupler a portion of said first modulated RF signal; mixing said received portion of said first modulated RF signal and said received second modulated RF signal to produce a modulated intermediate frequency (IF) signal having a modulated center frequency F3 equal to a difference |F1-F2| between said first carrier frequency F1 and said second carrier frequency F2; and receiving said second modulation signal M2 and in accordance therewith demodulating said modulated IF signal.
Claim 24
Dependent Claim
166 words
A data transceiving method for transmitting and receiving modulated radio frequency (RF) signals, comprising the steps of: receiving a first modulation signal M1 and generating a second modulation signal M2 therefrom; generating a RF signal having a first carrier frequency F1; modulating said RF signal in accordance with said first modulation signal M1; transmitting said modulated RF signal as a first modulated RF signal via an antenna; receiving via said antenna a second modulated RF signal having a second carrier frequency F2 modulated by a third modulation signal M3; receiving via a signal coupler a portion of said first modulated RF signal; mixing said received portion of said first modulated RF signal and said received second modulated RF signal to produce a modulated intermediate frequency (IF) signal having a modulated center frequency F3 equal to a difference |F1-F2| between said first carrier frequency F1 and said second carrier frequency F2; and receiving said second modulation signal M2 and in accordance therewith demodulating said modulated IF signal.
Claim 25
Dependent Claim
59 words
A data transceiving method as recited in claim 21, wherein said step of generating a RF signal having a first carrier frequency F1 comprises generating a frequency error signal in a phase-lock-loop which includes a frequency-controllable oscillator and combining said frequency error signal with said first modulation signal M1 to produce a frequency control signal for said frequency-controllable oscillator.
Claim 26
Dependent Claim
38 words
A data transceiving method as recited in claim 22, wherein said step of modulating said RF signal in accordance with said first modulation signal M1 comprises frequency-modulating said RF signal in accordance with said first modulation signal M1.
Claim 27
Dependent Claim
41 words
A data transceiving method as recited in claim 22, wherein said step of modulating said RF signal in accordance with said first modulation signal M1 comprises modulating said RF signal with said second modulation signal M2 as said frequency control signal.
Claim 28
Dependent Claim
37 words
A data transceiving method as recited in claim 21, wherein said step of receiving via a signal coupler a portion of said first modulated RF signal comprises receiving said first modulated RF signal portion via an attenuator.
Claim 29
Dependent Claim
58 words
A data transceiving method as recited in claim 21, wherein said step of mixing said received portion of said first modulated RF signal and said received second modulated RF signal to produce a modulated IF signal comprises inputting said first and second modulated RF signals to a single-input mixer on a single signal line from said signal coupler.
Claim 30
Dependent Claim
50 words
A data transceiving method as recited in claim 21, wherein said step of receiving said second modulation signal M2 and in accordance therewith demodulating said modulated IF signal comprises demodulating said modulated IF signal to produce a baseband signal and subtracting said second modulation signal M2 from said baseband signal.
Claim 31
Dependent Claim
30 words
A data transceiving method as recited in claim 27, wherein said step of demodulating said modulated IF signal to produce a baseband signal comprises frequency discriminating said modulated IF signal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-08-21 | 1999-02-20 | 1999-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-08-21 | 2003-02-20 | 2003-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-08-21 | 2007-02-20 | 2007-08-22 | $7700.00 | Window Closed / Lapsed |