US4523329A
Expired / Lapsed
US
⏱️ 0.0 years remaining
FM receiver
Assignee: Pioneer Corp
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Filing: 1983-09-06
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Granted: 1985-06-11
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Expires: 2003-09-06
Abstract
Abstract An FM receiver comprising a 90 degree phase shifter 21 of the FM signal and a first multiplier 22 for multiplying the FM signal and the phase shifted signal to produce a main signal L+R and a second multiplier 6 for multiplying the FM signal, the phase shifted signal and a subcarrier wave of 38 kHz to produce a sub-signal L-R.
Inventors
- 👤 Kohji Ishida
- 👤 Tatsuo Numata
- 👤 Masaharu Sakamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:33
CPC Classifications
H; H03; H03D; H03D1/00; H03D1/22; H03D1/2209; H03D1/2236
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
92 words
An FM receiver, comprising: a phase shifter (21) for shifting the phase of an incoming FM signal by an amount corresponding to the frequency of said FM signal; a first multiplier (22) for multiplying said incoming FM signal and the output of said phase shifter, thereby producing a main signal (L+R); a generator of an FM subcarrier wave; and a second multiplier (6), connected in parallel with said first multiplier, for multiplying said FM signal, the output of said phase shifter, and the output of said generator thereby producing a subsignal (L-R).
Claim 2
Dependent Claim
92 words
An FM receiver, comprising: a phase shifter (21) for shifting the phase of an incoming FM signal by an amount corresponding to the frequency of said FM signal; a first multiplier (22) for multiplying said incoming FM signal and the output of said phase shifter, thereby producing a main signal (L+R); a generator of an FM subcarrier wave; and a second multiplier (6), connected in parallel with said first multiplier, for multiplying said FM signal, the output of said phase shifter, and the output of said generator thereby producing a subsignal (L-R).
Claim 3
Dependent Claim
26 words
An FM receiver, as recited in claim 1, wherein said phase shifter shifts the phase by 90 degrees of a center FM frequency (ω o ).
Claim 4
Dependent Claim
24 words
An FM receiver, as recited in claim 1, wherein said generator is a phase-locked loop (41) connected to the output of said first multiplier.
Claim 5
Dependent Claim
31 words
An FM receiver, as recited in claim 1, further comprising a matrix circuit (5) connected to the outputs of said first and second multipliers for separating left and right signals (L,R).
Claim 6
Dependent Claim
31 words
An FM receiver, as recited in claim 3, further comprising a matrix circuit (5) connected to the outputs of said first and second multipliers for separating left and right signals (L,R).
Claim 7
Dependent Claim
21 words
An FM receiver, as recited in claim 1, further comprising a limiter (1) for limiting the amplitude of said FM signal.
Claim 8
Dependent Claim
21 words
An FM receiver, as recited in claim 5, further comprising a limiter (1) for limiting the amplitude of said FM signal.
Claim 9
Dependent Claim
23 words
An FM receiver, as recited in claim 6, wherein said phase-locked loop produces a subcarrier wave substantially at a frequency of 38 kHz.
References Cited (Backward Citations)
US4063042A
Cited
US4117410A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-06-10 | 1988-12-10 | 1989-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-10 | 1992-12-10 | 1993-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-10 | 1996-12-10 | 1997-06-11 | $7700.00 | Window Closed / Lapsed |