Patent US4908615A successfully refreshed from Google Patents.
US4908615A
Expired / Lapsed
US
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Traffic light control system and method
Assignee: Texas Instruments Inc
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Filing: 1988-08-09
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Granted: 1990-03-13
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Expires: 2008-08-09
Abstract
Abstract Preferred embodiments include a radar traffic light control system with a transmitter/receiver module including an array (103) of interconnected microstrip patch antennas (38) which also act as the resonators for oscillators powered by IMPATT diodes (34, 36); varactors (158) on the interconnections permit beam steering for scanning roadways.
Inventors
- 👤 Burhan Bayraktaroglu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:03
CPC Classifications
H; H03; H03B; H03B9/00; H03B9/12; H03B9/14; H03B9/147; G; G01; G01S; G01S13/00; G01S13/88; G01S13/91; H10; H10W; H10W72/00; H10W72/30; H03B2009/126; H03B2200/00; H03B2200/006; H03B2200/0074; H03B7/00; H03B7/02; H03B7/06; H03B7/08; H10D; H10D84/00; H10D84/01; H10D84/02; H10D84/05; H10W70/00; H10W70/60; H10W70/67; H10W70/68; H10W70/682; H10W70/685; H10W72/851; H10W72/874; H10W72/884; H10W90/00; H10W90/701; H10W90/751; H10W90/754
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
101 words
A traffic light control system, comprising: (a) a transmitter/receiver, said transmitter/receiver for transmitting a beam towards a roadway, detecting reflections of said beam from vehicles on said roadway, and outputting a detection signal; and (b) circuitry connected to said transmitter/receiver, said circuitry converting said detection signal into traffic light control signals; (c) said transmitter/receiver including an array of active antennas, each of said active antennas having: i. an oscillator including a power source and a resonator; and ii. a radiator coinciding with said resonator; (d) said transmitter/receiver further including interconnections among said active antennas, said interconnections coupling said active antennas together.
Claim 2
Dependent Claim
101 words
A traffic light control system, comprising: (a) a transmitter/receiver, said transmitter/receiver for transmitting a beam towards a roadway, detecting reflections of said beam from vehicles on said roadway, and outputting a detection signal; and (b) circuitry connected to said transmitter/receiver, said circuitry converting said detection signal into traffic light control signals; (c) said transmitter/receiver including an array of active antennas, each of said active antennas having: i. an oscillator including a power source and a resonator; and ii. a radiator coinciding with said resonator; (d) said transmitter/receiver further including interconnections among said active antennas, said interconnections coupling said active antennas together.
Claim 3
Dependent Claim
27 words
The system of claim 1, wherein: (a) said active antennas are imbedded in a transmission line network; and (b) said interconnections include transmission lines of said network.
Claim 4
Dependent Claim
39 words
The system of claim 1, wherein: (a) said power source is a plurality of IMPATT diodes biased into breakdown; (b) said resonator is a microstrip patch; and (c) said diodes and patch are formed on a single semiconductor substrate.
Claim 5
Dependent Claim
56 words
The system of claim 3, wherein: (a) said substrate is gallium arsenide with a metallized ground plane on the backside; (b) said diodes are formed on mesas on said substrate; (c) said diodes are connected to said patch by air bridges; and (d) said diodes are connected to said ground plane through vias in said substrate.
Claim 6
Dependent Claim
26 words
The system of claim 1, further comprising: (a) varactors connected to said interconnections, whereby beam steering may be achieved by changing electrical lengths of said interconnections.
Claim 7
Dependent Claim
27 words
The system of claim 5, wherein: (a) each of said active antennas is formed on a single substrate; and (b) said varactors are located on said substrates.
Claim 8
Dependent Claim
19 words
The system of claim 1, further comprising: (a) a mechanical actuator attached to said array for steering said beam.
Claim 9
Dependent Claim
43 words
The system of claim 1, further comprising: (a) varactors connected to said interconnections; and (b) a mechanical actuator attached to said array; (c) whereby beam steering may be achieved by changing electrical lengths of said interconnections and changing the orientation of said array.
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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) | 1993-03-12 | 1993-09-11 | 1994-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-12 | 1997-09-11 | 1998-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-12 | 2001-09-11 | 2002-03-13 | $7700.00 | Window Closed / Lapsed |