US5481572A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and apparatus for reducing the complexitiy of a diversity combining and sequence estimation receiver
Assignee: Unwired Planet LLC
•
Filing: 1994-08-02
•
Granted: 1996-01-02
•
Expires: 2014-08-02
Abstract
Abstract Signals in synchronizing sequences and data sequences are transmitted over a fading channel to a sequence estimation receiver. The signals are received by a plurality of mutually separated antennas and sampled to produce received antenna signals (S in ,r (k)). Using the received antenna signals, part transmission channel estimates (h est ,r) are formed for each antenna. These part channel estimates are used to form precomputed metric values (f a ,r ((ΔT ij ),g a (ΔT ij )). For the sequence estimation algorithm, branch metric values (m(ΔT ij ,k)) are formed by combining the precomputed metric values with the received antenna signals for state transitions (ΔT ij ). For one state transition there is formed a metric value such as the sum of a metric value (M(T j ,k-1)) for an old state (T j ) at a preceeding sampling time point (k-1) with a branch metric value (m(ΔT ij ,k)). Corresponding metric values are formed for all state transitions to the new state (T i ) and the state corresponding to the smallest of these metric values is chosen in accordance with the sequence estimation algorithm.
Inventors
- 👤 Johan Skold
- 👤 Per-Olof Eriksson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:19
CPC Classifications
H; H04; H04B; H04B7/00; H04B7/02; H04B7/04; H04B7/08; H04B7/0837; H04B7/0842; H04B7/0845; H04L; H04L1/00; H04L1/02
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
110 words
A method for reducing the influence of signal fading and time dispersion in a radio communication system, comprising the steps of: a) generating and transmitting a signal representing a transmitted symbol sequence; b) receiving the signal on at least two mutually separated antennas; c) sampling the signals received from the antennas to form received antenna signals; d) determining channel estimates for each of said antennas using said received antenna signals; e) processing said channel estimates to form precomputed metric values; f) forming branch metrics using said precomputed metric values and said received antenna signals; and g) estimating said transmitted symbol sequence using a sequence estimation algorithm employing said branch metrics.
Claim 2
Independent Claim
110 words
A method for reducing the influence of signal fading and time dispersion in a radio communication system, comprising the steps of: a) generating and transmitting a signal representing a transmitted symbol sequence; b) receiving the signal on at least two mutually separated antennas; c) sampling the signals received from the antennas to form received antenna signals; d) determining channel estimates for each of said antennas using said received antenna signals; e) processing said channel estimates to form precomputed metric values; f) forming branch metrics using said precomputed metric values and said received antenna signals; and g) estimating said transmitted symbol sequence using a sequence estimation algorithm employing said branch metrics.
Claim 3
Dependent Claim
14 words
The method of claim 1, wherein said sequence estimation algorithm is a Viterbi algorithm.
Claim 4
Dependent Claim
14 words
The method of claim 1, wherein said sampling is effected using log-polar signal processing.
Claim 5
Independent Claim
129 words
A method for reducing the influence of signal fading and time dispersion in a radio communication system, comprising the steps of: a) generating and transmitting a signal representing a transmitted symbol sequence; b) receiving the signal on at least two mutually separated antennas; c) sampling the signals received from the antennas to form received antenna signals; d) determining channel estimates for each of said antennas using said received antenna signals; e) generating symbol sequences and processing said channel estimates with said symbol sequences to produce assumed received signals; f) processing said assumed received signals to form precomputed metric values; g) forming branch metrics using .said precomputed metric values and said received antenna signals; and h) estimating said transmitted symbol sequence using a sequence estimation algorithm employing said branch metrics.
Claim 6
Independent Claim
129 words
A method for reducing the influence of signal fading and time dispersion in a radio communication system, comprising the steps of: a) generating and transmitting a signal representing a transmitted symbol sequence; b) receiving the signal on at least two mutually separated antennas; c) sampling the signals received from the antennas to form received antenna signals; d) determining channel estimates for each of said antennas using said received antenna signals; e) generating symbol sequences and processing said channel estimates with said symbol sequences to produce assumed received signals; f) processing said assumed received signals to form precomputed metric values; g) forming branch metrics using .said precomputed metric values and said received antenna signals; and h) estimating said transmitted symbol sequence using a sequence estimation algorithm employing said branch metrics.
Claim 7
Dependent Claim
14 words
The method of claim 4, wherein said sequence estimation algorithm is a Viterbi algorithm.
Claim 8
Dependent Claim
14 words
The method of claim 4, wherein said sampling is effected using log-polar signal processing.
Claim 9
Independent Claim
116 words
An apparatus for reducing the influence of fading and time dispersion, comprising; transmitter means for generating and transmitting a signal representing a transmitted symbol sequence; receiving means for receiving the signal on at least two mutually separated antennas; analog to digital converter means for sampling the signals received from said antennas to form received antenna signals; channel estimation means coupled to the received antenna signals for determining channel estimates for each of said antennas using said received antenna signals; metric calculating means for processing said channel estimates to form precomputed metric values; and analyzer means for estimating said transmitted symbol sequence using a sequence estimation algorithm employing said received antenna signals and said precomputed metric values.
Claim 10
Independent Claim
116 words
An apparatus for reducing the influence of fading and time dispersion, comprising; transmitter means for generating and transmitting a signal representing a transmitted symbol sequence; receiving means for receiving the signal on at least two mutually separated antennas; analog to digital converter means for sampling the signals received from said antennas to form received antenna signals; channel estimation means coupled to the received antenna signals for determining channel estimates for each of said antennas using said received antenna signals; metric calculating means for processing said channel estimates to form precomputed metric values; and analyzer means for estimating said transmitted symbol sequence using a sequence estimation algorithm employing said received antenna signals and said precomputed metric values.
Claim 11
Dependent Claim
14 words
The apparatus of claim 7, wherein said sequence estimation algorithm is a Viterbi algorithm.
Claim 12
Dependent Claim
14 words
The apparatus of claim 7, wherein said sampling is effected using log-polar signal processing.
Claim 13
Independent Claim
152 words
An apparatus for reducing the influence of signal fading and time dispersion in a radio communication system, comprising: transmitter means for generating and transmitting a signal representing a transmitted symbol sequence; receiver means for receiving the signal on at least two mutually separated antennas; analog to digital conversion means for sampling the signal received from the antennas to form received antenna signals; channel estimation means coupled to the received antenna signals for determining channel estimates for each of said antennas using said received antenna signals; symbol sequence generation means for generating symbol sequences and processing said channel estimates with said symbol sequences to produce assumed received signals; processor means for processing said assumed received signals to form precomputed metric values and forming branch metrics using said precomputed metric values and said received antenna signals; and analyzer means for estimating said transmitted symbol sequences using a sequence estimation algorithm employing said branch metrics.
Claim 14
Independent Claim
152 words
An apparatus for reducing the influence of signal fading and time dispersion in a radio communication system, comprising: transmitter means for generating and transmitting a signal representing a transmitted symbol sequence; receiver means for receiving the signal on at least two mutually separated antennas; analog to digital conversion means for sampling the signal received from the antennas to form received antenna signals; channel estimation means coupled to the received antenna signals for determining channel estimates for each of said antennas using said received antenna signals; symbol sequence generation means for generating symbol sequences and processing said channel estimates with said symbol sequences to produce assumed received signals; processor means for processing said assumed received signals to form precomputed metric values and forming branch metrics using said precomputed metric values and said received antenna signals; and analyzer means for estimating said transmitted symbol sequences using a sequence estimation algorithm employing said branch metrics.
Claim 15
Dependent Claim
14 words
The apparatus of claim 10, wherein said sequence estimation algorithm is a Viterbi algorithm.
Claim 16
Dependent Claim
14 words
The apparatus of claim 10, wherein said sampling is effected using log-polar signal processing.
References Cited (Backward Citations)
US4644562A
Cited
US4992798A
Cited
US5048059A
Cited
US5164961A
Cited
US5031193A
Cited
US5191598A
Cited
US5202903A
Cited
US5303263A
Cited
EP0543328A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-01-01 | 1999-07-03 | 2000-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-01-01 | 2003-07-03 | 2004-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-01-01 | 2007-07-03 | 2008-01-02 | $7700.00 | Window Closed / Lapsed |