US5179729A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tuner station selecting apparatus
Assignee: Panasonic Holdings Corp
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Filing: 1990-02-20
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Granted: 1993-01-12
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Expires: 2010-02-20
Abstract
Abstract A tuner station apparatus includes a first mixer for combining an input signal and a first local oscillation signal, and a second mixer for combining an output of the first mixer and a second local oscillation signal. The first and second local oscillation signals are generated by first and second PLL circuits, respectively. Each of the first and second PLL circuits include a frequency divider, a variable frequency divider, a phase comparator, a low pass filter, and a voltage controlled oscillator. The frequency divider of the first PLL circuit has a higher frequency division ratio than that of the second PLL circuit.
Inventors
- 👤 Akira Mishima
- 👤 Kazuhiko Kubo
- 👤 Akira Usui
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 08:50
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/44; H04N5/50; H03; H03D; H03D7/00; H03D7/16; H03D7/161; H03D7/163; H03J; H03J5/00; H03J5/02; H03J5/0245; H03J5/0272; H03B; H03B21/00; H03B21/01; H03B21/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
327 words
A tuner station apparatus comprising: a first mixer for combining an input signal and a first local oscillation signal; a second mixer for combining an output of said first mixer and a second local oscillation signal; a first PLL circuit including (a) a first voltage controlled oscillator for generating the first local oscillation signal, (b) a first frequency divider for frequency dividing in accordance with a fixed first frequency division ratio 1:N the first local oscillation signal output by said first voltage controlled oscillator, (c) a first variable frequency divider for frequency dividing in accordance with a first variable frequency division ratio an output of said first frequency divider, (d) a first phase comparator for comparing an output of said first variable frequency divider and a reference signal, and (e) a first low-pass filter having input thereto an output of said first phase comparator and outputting a first voltage control signal for said first voltage controlled oscillator; and, a second PLL circuit including (a) a second voltage controlled oscillator for generating the second local oscillation signal, (b) a second frequency divider for frequency dividing in accordance with a fixed second frequency division ratio 1:M the second local oscillation signal output by said second voltage controlled oscillator, (c) a second variable frequency divider for frequency dividing in accordance with a second variable frequency division ratio an output of said second frequency divider, (d) a second phase comparator for comparing an output of said first variable frequency divider and the reference signal, and (e) a second low-pass filter having input thereto an output of said second phase comparator and outputting a second voltage control signal for said second voltage controlled oscillator; wherein M<N, and wherein a value of N is such that a high frequency disturbance of the input signal caused by said first PLL circuit is relatively small, and wherein a value of M is such that a fine tuning adjustment of the second PLL circuit is facilitated.
Claim 2
Dependent Claim
327 words
A tuner station apparatus comprising: a first mixer for combining an input signal and a first local oscillation signal; a second mixer for combining an output of said first mixer and a second local oscillation signal; a first PLL circuit including (a) a first voltage controlled oscillator for generating the first local oscillation signal, (b) a first frequency divider for frequency dividing in accordance with a fixed first frequency division ratio 1:N the first local oscillation signal output by said first voltage controlled oscillator, (c) a first variable frequency divider for frequency dividing in accordance with a first variable frequency division ratio an output of said first frequency divider, (d) a first phase comparator for comparing an output of said first variable frequency divider and a reference signal, and (e) a first low-pass filter having input thereto an output of said first phase comparator and outputting a first voltage control signal for said first voltage controlled oscillator; and, a second PLL circuit including (a) a second voltage controlled oscillator for generating the second local oscillation signal, (b) a second frequency divider for frequency dividing in accordance with a fixed second frequency division ratio 1:M the second local oscillation signal output by said second voltage controlled oscillator, (c) a second variable frequency divider for frequency dividing in accordance with a second variable frequency division ratio an output of said second frequency divider, (d) a second phase comparator for comparing an output of said first variable frequency divider and the reference signal, and (e) a second low-pass filter having input thereto an output of said second phase comparator and outputting a second voltage control signal for said second voltage controlled oscillator; wherein M<N, and wherein a value of N is such that a high frequency disturbance of the input signal caused by said first PLL circuit is relatively small, and wherein a value of M is such that a fine tuning adjustment of the second PLL circuit is facilitated.
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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) | 1996-01-12 | 1996-07-13 | 1997-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-01-12 | 2000-07-13 | 2001-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-01-12 | 2004-07-13 | 2005-01-12 | $7700.00 | Window Closed / Lapsed |