US4373210A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Space diversity combiner
Assignee: AT&T Inc
•
Filing: 1981-03-27
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Granted: 1983-02-08
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Expires: 2001-03-27
Abstract
Abstract The benefits of space diversity combining in the presence of interference has been found to depend upon the signal-to-interference ratios at the two antennas. For optimum results, the signal-to-interference ratios should not differ by more than ±3 dB. If they do, an attenuator (12) is included in the antenna circuit (10) having the poorer signal-to-interference ratio so as to reduce the signal contribution from that antenna. Optimum signal conditions are disclosed.
Inventors
- 👤 Peter D. Karabinis
- 👤 Hotze Miedema
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:29
CPC Classifications
H; H04; H04B; H04B7/00; H04B7/02; H04B7/04; H04B7/08; H04B7/0837; H04B7/0842; H04B7/0848; H04B7/0857
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
126 words
A space diversity combiner comprising: first and second antenna circuits (10, 11); means (15) for combining the signals (S 1 and S 2 ) in said circuits in a common output circuit (19); and attenuating means (12) disposed in the antenna circuit (10) having the smaller signal-to-interference ratio (S 1 /I 1 ); said attenuator being adjusted to reduce the contribution of the signal (S 1 ) in the antenna circuit (10) having the smaller signal-to-interference ratio such that the attenuated signal power S 1 ' at the input of said combining means (15) is given by S.sub.1 '/S.sub.2 =(S.sub.1 /I.sub.1)/S.sub.2 /I.sub.2 where S 1 /I 1 and S 2 /I 2 are the signal-to-interference power ratios for the two antennas; and S.sub.1 /I.sub.1 <S.sub.2 /I.sub.2.
Claim 2
Dependent Claim
126 words
A space diversity combiner comprising: first and second antenna circuits (10, 11); means (15) for combining the signals (S 1 and S 2 ) in said circuits in a common output circuit (19); and attenuating means (12) disposed in the antenna circuit (10) having the smaller signal-to-interference ratio (S 1 /I 1 ); said attenuator being adjusted to reduce the contribution of the signal (S 1 ) in the antenna circuit (10) having the smaller signal-to-interference ratio such that the attenuated signal power S 1 ' at the input of said combining means (15) is given by S.sub.1 '/S.sub.2 =(S.sub.1 /I.sub.1)/S.sub.2 /I.sub.2 where S 1 /I 1 and S 2 /I 2 are the signal-to-interference power ratios for the two antennas; and S.sub.1 /I.sub.1 <S.sub.2 /I.sub.2.
Claim 3
Dependent Claim
39 words
The combiner according to claim 1 including phase control means (13, 14, 16) for varying the relative phase of the two signals (S 1 , S 2 ) so that they combine in phase in the signal combiner (15).
References Cited (Backward Citations)
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Cited
US3167761A
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US3633107A
Cited
US4075566A
Cited
US4100496A
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US4160952A
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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) | 1986-02-07 | 1986-08-09 | 1987-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-07 | 1990-08-09 | 1991-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-07 | 1994-08-09 | 1995-02-08 | $7700.00 | Window Closed / Lapsed |