US4592074A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Simplified hardware implementation of a digital IF translator
Assignee: Boeing North American Inc
•
Filing: 1984-06-01
•
Granted: 1986-05-27
•
Expires: 2004-06-01
Abstract
Abstract There is disclosed an implementation of a digital intermediate frequency (IF) translator which accepts a digital converted IF input and performs a complex mix to produce an IF baseband output in I (in-phase) and Q (quadrature phase) format. The translator reduces the sampling rate and provides filtering to produce I and Q components which can be subsequently utilized to derive the information contained in the original analog input signal. The translator is implemented with a configuration which simplifies the complex mix required to produce I and Q components and accumulates the samples to provide boxcar filtering prior to providing the I and Q components as outputs at a reduced sampling rate.
Inventors
- 👤 J. William Whikehart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:10
CPC Classifications
H; H03; H03D; H03D3/00; H03D3/007; H03D3/006
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
123 words
A digital translator comprising: means for sampling a digital input signal sequence representing a digital intermediate frequency at a sampling rate; means for selecting samples of said input sequence to form a first channel sample sequence and a second channel sample sequence; first means for summing a predetermined number of samples of said first channel sample sequence to provide an in-phase channel output of said digital input signal; second means for summing the first and last samples of a predetermined number of said second channel sample sequence to provide a sum output; and third means for summing a predetermined number of samples of said second sample sequence with said sum output to provide a quadrature phase channel output of said digital input signal.
Claim 2
Dependent Claim
123 words
A digital translator comprising: means for sampling a digital input signal sequence representing a digital intermediate frequency at a sampling rate; means for selecting samples of said input sequence to form a first channel sample sequence and a second channel sample sequence; first means for summing a predetermined number of samples of said first channel sample sequence to provide an in-phase channel output of said digital input signal; second means for summing the first and last samples of a predetermined number of said second channel sample sequence to provide a sum output; and third means for summing a predetermined number of samples of said second sample sequence with said sum output to provide a quadrature phase channel output of said digital input signal.
Claim 3
Dependent Claim
42 words
The system of claim 1 wherein said first and third means for summing is an accumulator which is coupled to add successive samples of said sample sequence to the sum of previous samples of said sample sequence over a predetermined frame interval.
Claim 4
Dependent Claim
19 words
The system of claim 2 further including means for clearing said accumulator at the beginning of each frame interval.
Claim 5
Dependent Claim
32 words
The system of claim 2 wherein said first and third means for summing is constructed and arranged to accumulate at a rate less than the sampling rate of said means for sampling.
Claim 6
Dependent Claim
164 words
In a communications system having means for receiving a communications signal, means for converting that communications signal into an intermediate frequency, and means for translating said intermediate frequency to a lower intermediate frequency prior to signal processing, the improvement in said means for translating comprising: means for sampling a digital input signal sequence representing a digital intermediate frequency at a sampling rate; means for selecting samples of said input sequence to form a first channel sample sequence and a second channel sample sequence; first means for summing a predetermined number of samples of said first channel sample sequence to provide an in-phase channel output of said digital input signal; second means for summing the first and last samples of a predetermined number of said second channel sample sequence to provide a sum output; and third means for summing a predetermined number of samples of said second sample sequence with said sum output to provide a quadrature phase channel output of said digital input signal.
Claim 7
Dependent Claim
164 words
In a communications system having means for receiving a communications signal, means for converting that communications signal into an intermediate frequency, and means for translating said intermediate frequency to a lower intermediate frequency prior to signal processing, the improvement in said means for translating comprising: means for sampling a digital input signal sequence representing a digital intermediate frequency at a sampling rate; means for selecting samples of said input sequence to form a first channel sample sequence and a second channel sample sequence; first means for summing a predetermined number of samples of said first channel sample sequence to provide an in-phase channel output of said digital input signal; second means for summing the first and last samples of a predetermined number of said second channel sample sequence to provide a sum output; and third means for summing a predetermined number of samples of said second sample sequence with said sum output to provide a quadrature phase channel output of said digital input signal.
References Cited (Backward Citations)
US2965849A
Cited
US3384828A
Cited
US3634773A
Cited
US3908114A
Cited
US4130806A
Cited
US4393352A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-05-26 | 1989-11-25 | 1990-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-26 | 1993-11-25 | 1994-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-26 | 1997-11-25 | 1998-05-27 | $7700.00 | Window Closed / Lapsed |