US5113446A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stereo blend controller for FM receivers
Assignee: Visteon Global Technologies Inc
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Filing: 1990-12-17
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Granted: 1992-05-12
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Expires: 2010-12-17
Abstract
Abstract The stereo separation provided by a radio receiver is controlled in dependence on the radio frequency environment at the receiver antenna. The blend curve for determining stereo separation in dependence on the field intensity of a received signal is dynamically shifted to maintain the average magnitude of a blend control signal at a predetermined magnitude if the field intensity is above a threshold. Otherwise the blend control signal follows a lower limit blend curve of predetermined shape.
Inventors
- 👤 John F. Kennedy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:32
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/1646; H04B1/1661; H04B1/1669; H04B1/1676
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
108 words
A stereo blend controller for a stereo radio receiver which converts stereo broadcast signals to blended-stereo audio signals, said controller comprising: level detecting means for generating a field intensity signal indicative of the intensity at which a stereo broadcast signal is received; blend curve generator means coupled to said level detecting means for generating a blend control signal according to a blend curve and said field intensity signal; and curve shift means coupled to said level detecting means and said blend curve generator means for substantially maintaining the average magnitude of said blend control signal at a predetermined magnitude if said field intensity signal is above a threshold.
Claim 2
Dependent Claim
108 words
A stereo blend controller for a stereo radio receiver which converts stereo broadcast signals to blended-stereo audio signals, said controller comprising: level detecting means for generating a field intensity signal indicative of the intensity at which a stereo broadcast signal is received; blend curve generator means coupled to said level detecting means for generating a blend control signal according to a blend curve and said field intensity signal; and curve shift means coupled to said level detecting means and said blend curve generator means for substantially maintaining the average magnitude of said blend control signal at a predetermined magnitude if said field intensity signal is above a threshold.
Claim 3
Dependent Claim
25 words
The controller of claim 1 wherein said curve shift means includes a variable attenuator for variably attenuating said field intensity signal to maintain said average.
Claim 4
Dependent Claim
29 words
The controller of claim 1 wherein said curve shift means includes an integral-derivative controller for comparing said blend control signal with said predetermined magnitude to generate a correction signal.
Claim 5
Dependent Claim
32 words
The controller of claim 3 wherein said curve shift means further includes a variable attenuator for variably attenuating said field intensity signal in response to said correction signal to maintain said average.
Claim 6
Dependent Claim
19 words
The controller of claim 1 wherein said predetermined magnitude corresponds to a separation less than the maximum stereo separation.
Claim 7
Dependent Claim
16 words
The controller of claim 5 wherein said predetermined magnitude provides about 35 dB of stereo separation.
Claim 8
Dependent Claim
19 words
The controller of claim 1 wherein said curve shift means includes a lower limit for shifting said blend curve.
Claim 9
Dependent Claim
148 words
A stereo radio receiver for converting stereo broadcast signals to blended-stereo audio signals comprising: demodulating means for receiving, amplifying, and demodulating a stereo broadcast signal; level detecting means coupled to said demodulating means for generating a field intensity signal indicative of the intensitY at which said stereo broadcast signal is received; blend curve generator means coupled to said level detecting means for generating a blend control signal according to a blend curve and said field intensity signal; stereo decoder means coupled to said demodulating means and to said blend curve generator means for producing said stereo audio signals having a stereo separation responsive to said blend control signal; and curve shift means coupled to said level detecting means and said blend curve generator means for substantially maintaining the average magnitude of said blend control signal at a predetermined magnitude if said field intensity signal is above a threshold.
Claim 10
Dependent Claim
148 words
A stereo radio receiver for converting stereo broadcast signals to blended-stereo audio signals comprising: demodulating means for receiving, amplifying, and demodulating a stereo broadcast signal; level detecting means coupled to said demodulating means for generating a field intensity signal indicative of the intensitY at which said stereo broadcast signal is received; blend curve generator means coupled to said level detecting means for generating a blend control signal according to a blend curve and said field intensity signal; stereo decoder means coupled to said demodulating means and to said blend curve generator means for producing said stereo audio signals having a stereo separation responsive to said blend control signal; and curve shift means coupled to said level detecting means and said blend curve generator means for substantially maintaining the average magnitude of said blend control signal at a predetermined magnitude if said field intensity signal is above a threshold.
Claim 11
Dependent Claim
25 words
The receiver of claim 8 wherein said curve shift means includes a variable attenuator for variably attenuating said field intensity signal to maintain said average.
Claim 12
Dependent Claim
29 words
The receiver of claim 8 wherein said curve shift means includes an integral-derivative controller for comparing said blend control signal with said predetermined magnitude to generate a correction signal.
Claim 13
Dependent Claim
32 words
The receiver of claim 10 wherein said curve shift means further includes a variable attenuator for variably attenuating said field intensity signal in response to said correction signal to maintain said average.
Claim 14
Dependent Claim
19 words
The receiver of claim 8 wherein said predetermined magnitude corresponds to a separation less than the maximum stereo separation.
Claim 15
Dependent Claim
16 words
The receiver of claim 12 wherein said predetermined magnitude provides about 35 dB of stereo separation.
Claim 16
Dependent Claim
19 words
The receiver of claim 8 wherein said curve shift means includes a lower limit for shifting said blend curve.
Claim 17
Dependent Claim
155 words
A stereo radio receiver for converting stereo broadcast signals to blended-stereo audio signals comprising: demodulating means for receiving, amplifying, and demodulating a stereo broadcast signal; level detecting means coupled to said demodulating means for generating a field intensity signal indicative of the intensity at which said stereo broadcast signal is received; curve generator means coupled to said level detecting means for generating a blend control signal in response to said field intensity signal; stereo decoder means coupled to said demodulating means and to said curve generator means for producing said stereo audio signals having a stereo separation responsive to said blend control signal; an integral-derivative controller coupled to said curve generator means, said integral-derivative controller comparing said blend control signal with a predetermined magnitude to generate a correction signal; and variable attenuator means coupled to said integral-derivative controller and said level detecting means for attenuating said field intensity signal in response to said correction signal.
Claim 18
Dependent Claim
155 words
A stereo radio receiver for converting stereo broadcast signals to blended-stereo audio signals comprising: demodulating means for receiving, amplifying, and demodulating a stereo broadcast signal; level detecting means coupled to said demodulating means for generating a field intensity signal indicative of the intensity at which said stereo broadcast signal is received; curve generator means coupled to said level detecting means for generating a blend control signal in response to said field intensity signal; stereo decoder means coupled to said demodulating means and to said curve generator means for producing said stereo audio signals having a stereo separation responsive to said blend control signal; an integral-derivative controller coupled to said curve generator means, said integral-derivative controller comparing said blend control signal with a predetermined magnitude to generate a correction signal; and variable attenuator means coupled to said integral-derivative controller and said level detecting means for attenuating said field intensity signal in response to said correction signal.
Claim 19
Independent Claim
89 words
A method of controlling blend in a stereo radio receiver comprising the steps of: measuring the field intensity at which a stereo broadcast signal is received; converting said field intensity into a blend control signal having a voltage determined according to a blend curve having a predetermined shape; decoding said stereo broadcast signals to have a stereo separation determined by said blend control signal; and maintaining said blend control signal at a predetermined average magnitude to provide a predetermined average separation if said field intensity is above a threshold.
Claim 20
Independent Claim
89 words
A method of controlling blend in a stereo radio receiver comprising the steps of: measuring the field intensity at which a stereo broadcast signal is received; converting said field intensity into a blend control signal having a voltage determined according to a blend curve having a predetermined shape; decoding said stereo broadcast signals to have a stereo separation determined by said blend control signal; and maintaining said blend control signal at a predetermined average magnitude to provide a predetermined average separation if said field intensity is above a threshold.
Claim 21
Independent Claim
93 words
A method of controlling blend in a stereo radio receiver comprising the steps of: measuring the field intensity at which a stereo broadcast signal is received; converting said field intensity into a blend control signal according to a blend curve having a predetermined shape; decoding said stereo broadcast signals to have a stereo separation determined by said blend control signal; attenuating said field intensity signal prior to conversion into said blend control signal by an amount to cause the average magnitude of said blend control signal to be maintained at a predetermined magnitude.
Claim 22
Independent Claim
93 words
A method of controlling blend in a stereo radio receiver comprising the steps of: measuring the field intensity at which a stereo broadcast signal is received; converting said field intensity into a blend control signal according to a blend curve having a predetermined shape; decoding said stereo broadcast signals to have a stereo separation determined by said blend control signal; attenuating said field intensity signal prior to conversion into said blend control signal by an amount to cause the average magnitude of said blend control signal to be maintained at a predetermined magnitude.
Claim 23
Dependent Claim
29 words
The method of claim 17 further comprising the step of: integrating and differentiating said blend control signal to control the amount of said attenuation of said field intensity 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) | 1995-05-12 | 1995-11-11 | 1996-05-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-05-12 | 1999-11-11 | 2000-05-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-05-12 | 2003-11-11 | 2004-05-12 | $7700.00 | Window Closed / Lapsed |