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US4142155A
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Diversity system
Assignee: NTT Inc
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Filing: 1977-05-11
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Granted: 1979-02-27
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Expires: 1997-05-11
Abstract
Abstract A common baseband digital signal is applied to a plurality of frequency modulators generating frequency modulated signals the carrier frequencies of which are equal to that of a common reference frequency oscillator, and the peak frequency deviations of the frequency modulated signals are made slightly different from each other.
Inventors
- 👤 Fumiyuki Adachi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 15:22
CPC Classifications
H; H04; H04L; H04L1/00; H04L1/02; H04L1/04
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
102 words
A diversity system comprising (a) a reference frequency oscillator, (b) a plurality of frequency modulators each having means which generates frequency modulated signals the carrier frequencies of which are equal to each other and to that of said reference frequency oscillator, (c) said plurality of frequency modulators generating frequency modulated signals with a common baseband digital signal being applied to said plurality of frequency modulators in such a manner that the peak frequency deviations of said modulated signals are different from each other, and (d) the frequency modulated signals being transmitted from respective antennas connected to said plurality of frequency modulators, respectively.
Claim 2
Dependent Claim
102 words
A diversity system comprising (a) a reference frequency oscillator, (b) a plurality of frequency modulators each having means which generates frequency modulated signals the carrier frequencies of which are equal to each other and to that of said reference frequency oscillator, (c) said plurality of frequency modulators generating frequency modulated signals with a common baseband digital signal being applied to said plurality of frequency modulators in such a manner that the peak frequency deviations of said modulated signals are different from each other, and (d) the frequency modulated signals being transmitted from respective antennas connected to said plurality of frequency modulators, respectively.
Claim 3
Dependent Claim
25 words
A diversity system as set forth in claim 1 wherein each of said plurality of frequency modulators consists of an integrator and a phase modulator.
Claim 4
Dependent Claim
26 words
A diversity system as set forth in claim 1 wherein each of said plurality of frequency modulators consists of a combiner and a phase locked loop.
Claim 5
Dependent Claim
26 words
A diversity system as set forth in claim 3 wherein said phase locked loop consists of a voltage-controlled oscillator, a phase detector, and low pass filter.
Claim 6
Dependent Claim
32 words
A diversity system as set forth in claim 1, further comprising a receiver including a predetection filter having a bandwidth capable of receiving all of the modulated carriers transmitted from said transmitters.
Claim 7
Dependent Claim
32 words
A diversity system as set forth in claim 2, further comprising a receiver including a predetection filter having a bandwidth capable of receiving all of the modulated carriers transmitted from said transmitters.
Claim 8
Dependent Claim
51 words
A diversity system comprising: (a) at least two angularly modulating transmitters; (b) carriers in each transmitter being angularly modulated by a common baseband digital signal to different peak frequency deviations of said modulated carriers from each other; and (c) said modulated carriers being transmitted from respective antennas connected to each transmitter.
Claim 9
Dependent Claim
51 words
A diversity system comprising: (a) at least two angularly modulating transmitters; (b) carriers in each transmitter being angularly modulated by a common baseband digital signal to different peak frequency deviations of said modulated carriers from each other; and (c) said modulated carriers being transmitted from respective antennas connected to each transmitter.
Claim 10
Dependent Claim
54 words
A diversity system comprising: (a) at least two angularly modulating transmitters; (b) carriers of identical frequency in each transmitter being angularly modulated by a common baseband digital signal to different peak frequency deviations of said modulated carriers from each other; and (c) said modulated carriers being transmitted from respective antennas connected to each transmitter.
Claim 11
Dependent Claim
54 words
A diversity system comprising: (a) at least two angularly modulating transmitters; (b) carriers of identical frequency in each transmitter being angularly modulated by a common baseband digital signal to different peak frequency deviations of said modulated carriers from each other; and (c) said modulated carriers being transmitted from respective antennas connected to each transmitter.
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) | 1982-02-26 | 1982-08-28 | 1983-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-26 | 1986-08-28 | 1987-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-26 | 1990-08-28 | 1991-02-27 | $7700.00 | Window Closed / Lapsed |