US3757335A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Communication and control system
Assignee: Broadcom Inc
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Filing: 1968-02-29
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Granted: 1973-09-04
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Expires: 1988-02-29
Abstract
Abstract A retrodirective oscillating loop for a communication and control channel is disclosed for the transmission and reception of radiant energy waveforms between remotely located terminals wherein each terminal has a retrodirective property with respect to the waveform propagation in the channel. It is demonstrated herein that two retrodirective communications repeaters or terminals form a retrodirective oscillating loop if the signal transmitted by one terminal is received, sufficiently amplified, and transmitted back by the second terminal and again received, sufficiently amplified, and transmitted by the first terminal while remaining stationary in time. This provides an important capability for two retrodirective antenna array terminals of a retrodirective oscillating loop of automatically steering toward each other when each terminal is within the field of view of the other terminal. When a retrodirective oscillating loop is established between two remotely located antenna array terminals of an electromagnetic radiation spectrum communication and control channel, a carrier oscillation is initiated from the noise spectrum present in the apertures of each array when the input aperture of each terminal is within the field of view of the output aperture of the other terminal.
Inventors
- 👤 E Gruenberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 04:09
CPC Classifications
H; H01; H01Q; H01Q3/00; H01Q3/26; H01Q3/30; H01Q3/34; H01Q3/42; G; G01; G01S; G01S13/00; G01S13/02; G01S13/06; G01S13/08; G01S13/32; G01S13/36; G01S13/40; G01S13/74; G01S13/82; G01S13/84; H01Q15/00; H01Q3/44; H01Q3/46; H04; H04B; H04B7/00
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
153 words
A retrodirective oscillating loop comprising: first and second remotely located retrodirective antenna array terminals with respective retrodirective properties for received and transmitted propagating electromagnetic waveform energies which are spaced apart by an intervening medium which sustains propagation of said electromagnetic waveform energy, each of said terminals having an effective field of view for a respective noise spectrum and each of said terminals being disposed within the respective effective field of view of the other said terminal to form a communications loop; means for establishing total loop energy gain equal to or greater than total loop energy loss to cause a carrier waveform to be automatically built up out of noise in said loop without the initial transmission of a carrier from one of said terminals to the other of said terminals; and local oscillator means to provide a frequency difference between received waveforms and transmitted waveforms at at least one of said terminals.
Claim 2
Dependent Claim
153 words
A retrodirective oscillating loop comprising: first and second remotely located retrodirective antenna array terminals with respective retrodirective properties for received and transmitted propagating electromagnetic waveform energies which are spaced apart by an intervening medium which sustains propagation of said electromagnetic waveform energy, each of said terminals having an effective field of view for a respective noise spectrum and each of said terminals being disposed within the respective effective field of view of the other said terminal to form a communications loop; means for establishing total loop energy gain equal to or greater than total loop energy loss to cause a carrier waveform to be automatically built up out of noise in said loop without the initial transmission of a carrier from one of said terminals to the other of said terminals; and local oscillator means to provide a frequency difference between received waveforms and transmitted waveforms at at least one of said terminals.
Claim 3
Dependent Claim
61 words
A retrodirective oscillating loop as set forth in claim 1 wherein said means at one of said terminals provides a frequency difference between a received waveform and the corresponding transmitted waveform includes: means for converting the frequency of said received waveform to another frequency; means for amplifying said other frequency; and means for converting said other frequency to said transmitted frequency.
Claim 4
Dependent Claim
18 words
A retrodirective oscillating loop as set forth in claim 2 wherein said other frequency is an intermediate frequency.
Claim 5
Dependent Claim
114 words
A retrodirective oscillating loop as set forth in claim 1 wherein said means at one of said terminals to provide a frequency difference between said received waveform and said corresponding transmitted waveform includes: means connected to a first set of antenna array elements of said one terminal for routing received oscillating signals through one amplifying channel to a second set of antenna array elements of said one terminal for transmission therefrom; and means for routing other received signals at said second set of antenna array elements through another amplifying channel to said first set of antenna array elements for transmission therefrom of another and different frequency than the frequency of said first received waveform.
Claim 6
Dependent Claim
80 words
A retrodirective oscillating loop as set forth in claim 1 wherein said means at one of said terminals to provide a frequency difference between said received waveform and said transmitted waveform includes: a local oscillator; means for mixing said received waveform with a higher frequency derived from said local oscillator and obtaining the subtracted resulting waveform; and means for transmitting said subtracted resulting waveforms to obtain an effective reversal of relative phase between said received waveforms and said transmitted waveforms.
Claim 7
Dependent Claim
43 words
A retrodirective oscillating loop as set forth in claim 5 including: means for converting the frequency of said received waveform to an intermediate frequency waveform; and means to subtract said intermediate frequency from said local oscillator higher frequency to obtain said transmitted frequency.
Claim 8
Dependent Claim
72 words
A retrodirective oscillating loop as set forth in claim 1 wherein said means at one of said terminals to provide a frequency difference between said received waveform and said transmitted waveform includes means to provide a phase inversion between said received waveform and said transmitted waveform at said one terminal only, the phase of the transmitted wave being the same as that of the received wave at the other of said terminals.
Claim 9
Dependent Claim
226 words
A retrodirective oscillating loop comprising: a. first and second remotely located retrodirective antenna array terminals, each terminal having retrodirective properties for transmitting a received waveform within the field of view of the terminal back in the direction from which the waveform was received; b. each of said retrodirective antenna array terminals being located in the field of view of the other terminal to form an oscillating communications loop in which a signal transmitted by one array terminal is received by the other array terminal and then transmitted back to the first array terminal; c. each of said antenna array terminals including a plurality of receiver and transmitter elements which are connected to each other by circuits having sufficient gain that the loop energy gain for a signal transmitted around the loop formed by said terminals is greater than the total loop energy loss, and the gain being sufficient that a carrier waveform is automatically built up out of noise in the loop including said first and second remotely located retrodirective antenna array terminals without the initial transmission of a carrier from one of said terminals to the other; and d. said circuits at at least one of said terminals including means to provide a frequency difference between the carrier waveform received at that terminal and the carrier waveform transmitted from that terminal to the other terminal.
Claim 10
Dependent Claim
226 words
A retrodirective oscillating loop comprising: a. first and second remotely located retrodirective antenna array terminals, each terminal having retrodirective properties for transmitting a received waveform within the field of view of the terminal back in the direction from which the waveform was received; b. each of said retrodirective antenna array terminals being located in the field of view of the other terminal to form an oscillating communications loop in which a signal transmitted by one array terminal is received by the other array terminal and then transmitted back to the first array terminal; c. each of said antenna array terminals including a plurality of receiver and transmitter elements which are connected to each other by circuits having sufficient gain that the loop energy gain for a signal transmitted around the loop formed by said terminals is greater than the total loop energy loss, and the gain being sufficient that a carrier waveform is automatically built up out of noise in the loop including said first and second remotely located retrodirective antenna array terminals without the initial transmission of a carrier from one of said terminals to the other; and d. said circuits at at least one of said terminals including means to provide a frequency difference between the carrier waveform received at that terminal and the carrier waveform transmitted from that terminal to the other terminal.
Claim 11
Dependent Claim
42 words
The oscillating loop of claim 8 wherein means are provided at both of said terminals for providing a frequency difference between the carrier wave form received at that terminal and the carrier waveform transmitted from that terminal back to the other terminal.
Claim 12
Dependent Claim
79 words
The oscillating loop of claim 9 wherein at one of said terminals the circuits connecting the receiver and transmitter elements, which include the means for providing a frequency difference between the received waveform and the transmitted waveform, provides a net inversion of the phase of the received waveform so that the phase of the carrier waveform transmitted from the elements at that terminal is inverted from the phase of the carrier waveform received by the elements at that terminal.
Claim 13
Dependent Claim
55 words
The oscillating loop of claim 10 wherein at the other of said terminals the circuits connecting the receiver and transmitter elements, which provide a frequency difference between the received waveform and the transmitted waveform, cause the transmitted carrier waveform to be transmitted without a net inversion of phase from the phase of the received waveform.
Claim 14
Dependent Claim
34 words
The oscillating loop of claim 11 wherein the circuits connecting the receiver and transmitter elements at said other terminal includes two local oscillators at which the carrier waveform is subtracted from a high frequency.
Claim 15
Dependent Claim
36 words
The oscillating loop of claim 8 wherein said circuits include phase inversion means for stAbilizing the frequencies of the carrier waveform built up in said loop against changes due to Doppler shift and local oscillator drift.
Claim 16
Dependent Claim
32 words
The oscillating loop of claim 8 wherein said circuits invert the phase of the received carrier waveform and transmit the carrier wave form with inverted phase at one only of said terminals.
Claim 17
Dependent Claim
33 words
The oscillating loop of claim 8 including a repeater for causing each of said terminals to be in the field of view of the other terminal and said communications loop includes said repeater.
Claim 18
Dependent Claim
132 words
A retrodirective oscillating loop comprising: first and second remotely located retrodirective antenna array terminals with respective retrodirective properties for received and transmitted propagating electromagnetic waveform energies which are spaced apart by an intervening medium which sustains propagation of said electromagnetic waveform energy, each of said terminals having an effective field of view for a respective noise spectrum and each of said terminals being disposed within the respective effective field of view of the other said terminal to form a communications loop; and means for establishing total loop energy gain equal to or greater than total loop energy loss to cause a carrier waveform to be automatically built up out of noise in said loop without the initial transmission of a carrier from one of said terminals to the other of said terminals.
Claim 19
Dependent Claim
132 words
A retrodirective oscillating loop comprising: first and second remotely located retrodirective antenna array terminals with respective retrodirective properties for received and transmitted propagating electromagnetic waveform energies which are spaced apart by an intervening medium which sustains propagation of said electromagnetic waveform energy, each of said terminals having an effective field of view for a respective noise spectrum and each of said terminals being disposed within the respective effective field of view of the other said terminal to form a communications loop; and means for establishing total loop energy gain equal to or greater than total loop energy loss to cause a carrier waveform to be automatically built up out of noise in said loop without the initial transmission of a carrier from one of said terminals to the other of said terminals.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |