US3609599A
Expired / Lapsed
US
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Time delay equalizer utilizing a plurality of cascaded directional filters
Assignee: AT&T Inc
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Filing: 1970-03-18
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Granted: 1971-09-28
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Expires: 1990-03-18
Abstract
Abstract This application discloses a microwave delay equalizer which utilizes a cascade of directional filters interconnected by delay networks. Control of the delay characteristic is achieved by appropriately selecting the center frequencies and response characteristics of the filters and the delay times of the interconnecting delay networks.
Inventors
- 👤 Robert Dean Standley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:59
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/04; H04B3/14; H04B3/141
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
160 words
A microwave delay equalizer for selectively delaying the frequency components of a broadband microwave input signal having a prescribed delay distortion characteristic comprising: a plurality of cascaded, four-port directional filters, each having a different center frequency, and each having two pairs of conjugate ports; delay networks connecting one port of each pair of conjugate ports of each filter to a different port of a different pair of conjugate ports of the next adjacent filter in said cascade of filters; each of said delay means introducing a prescribed average delay to compensate the delay distortion of said signal; resistive means terminating the other ports of the last of said filters in said cascade of filters; the other port of one of said pairs of ports of the first of said filters being the input port of said equalizer; and the other port of the other of said pairs of ports of said first filter being the output port of said equalizer.
Claim 2
Dependent Claim
160 words
A microwave delay equalizer for selectively delaying the frequency components of a broadband microwave input signal having a prescribed delay distortion characteristic comprising: a plurality of cascaded, four-port directional filters, each having a different center frequency, and each having two pairs of conjugate ports; delay networks connecting one port of each pair of conjugate ports of each filter to a different port of a different pair of conjugate ports of the next adjacent filter in said cascade of filters; each of said delay means introducing a prescribed average delay to compensate the delay distortion of said signal; resistive means terminating the other ports of the last of said filters in said cascade of filters; the other port of one of said pairs of ports of the first of said filters being the input port of said equalizer; and the other port of the other of said pairs of ports of said first filter being the output port of said equalizer.
Claim 3
Dependent Claim
19 words
A microwave delay equalizer in accordance with claim 1 in which said delay networks are lengths of transmission lines.
Claim 4
Dependent Claim
35 words
A microwave delay equalizer in accordance with claim 1 in which said center frequencies and the response characteristics of said filters define a frequency band substantially equivalent to the frequency band of said wave energy.
Claim 5
Dependent Claim
24 words
A microwave delay equalizer in accordance with claim 3 in which the response characteristics of adjacent filters overlap at about their half power points.
Claim 6
Dependent Claim
165 words
A microwave delay equalizer for selectively delaying the frequency components of a broadband microwave signal comprising: a network of directional filters; characterized in that each of said filters has a different center frequency, and in that each is a four port having two pairs of conjugate ports, wherein wave energy coupled to one port of one pair of conjugate ports will divide, in some predescribed manner, between the other pair of conjugate ports with no wave energy being coupled to the conjugate of said one port; a plurality of delay lines, where each delay line provides a different delay, and each connects one port of a conjugate pair of ports of a first filter to one port of a conjugate pair of ports of the next adjacent filter in said network; the remaining two ports of the last of said filters being match terminated; and the remaining two ports of the first of said filters constituting the input and output ports of said delay equalizer.
Claim 7
Dependent Claim
165 words
A microwave delay equalizer for selectively delaying the frequency components of a broadband microwave signal comprising: a network of directional filters; characterized in that each of said filters has a different center frequency, and in that each is a four port having two pairs of conjugate ports, wherein wave energy coupled to one port of one pair of conjugate ports will divide, in some predescribed manner, between the other pair of conjugate ports with no wave energy being coupled to the conjugate of said one port; a plurality of delay lines, where each delay line provides a different delay, and each connects one port of a conjugate pair of ports of a first filter to one port of a conjugate pair of ports of the next adjacent filter in said network; the remaining two ports of the last of said filters being match terminated; and the remaining two ports of the first of said filters constituting the input and output ports of said delay equalizer.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-27 | 1975-03-29 | 1975-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-27 | 1979-03-29 | 1979-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-27 | 1983-03-29 | 1983-09-28 | $7700.00 | Window Closed / Lapsed |