COMPREHENSIVE AUTOMATIC VEHICLE COMMUNICATION, PAGING, AND POSITION LOCATION SYSTEM
First Claim
Patent Images
1. A method of communicating between a first station and a second station comprising:
- a. transmitting from said first station on a single carrier frequency a sequence of a plurality of unique pairs of spaced binary code words, 1. the code words in each pair being identical, 2. each code word specifying a unique communication function, 3. the time interval between the code words in each pair being above or below a predetermined value, b. transmitting from said first station, on a local frequency determined by the length of said time interval, selected messages following code word pairs having time intervals above said predetermined value, code word pairs having time intervals below said predetermined value uniquely specifying a relatively brief message or command, c. receiving at said second station said single carrier frequency with a receiver having a first channel permanently tuned to said single carrier frequency, d. decoding selected pairs of the transmitted code words, e. generating, in response to a decoded selected pair of code words having a time interval below said predetermined value, a first signal for controlling a device, and f. generating, in response to a decoded seleCted pair of code words having a time interval above said perdetermined value, a second signal dependent on said time interval for automatically tuning a second channel in said receiver to said local frequency to receive said selected messages following code words pairs having time intervals above said predetermined value.
0 Assignments
0 Petitions
Accused Products
Abstract
A comprehensive electronic communication system for vehicles to permit transmission and reception of signals with respect to traffic warnings, crash warnings, emergency location signals, assistance signals, danger signals, and traffic advisories and the like, including a transmitter for repetitive transmitting on a single carrier frequency of a digital codeword and a receiver which provides controllable decoding and automatic receiver tuning means for automatically tuning a receiver to a predetermined local channel.
-
Citations
18 Claims
-
1. A method of communicating between a first station and a second station comprising:
- a. transmitting from said first station on a single carrier frequency a sequence of a plurality of unique pairs of spaced binary code words, 1. the code words in each pair being identical, 2. each code word specifying a unique communication function, 3. the time interval between the code words in each pair being above or below a predetermined value, b. transmitting from said first station, on a local frequency determined by the length of said time interval, selected messages following code word pairs having time intervals above said predetermined value, code word pairs having time intervals below said predetermined value uniquely specifying a relatively brief message or command, c. receiving at said second station said single carrier frequency with a receiver having a first channel permanently tuned to said single carrier frequency, d. decoding selected pairs of the transmitted code words, e. generating, in response to a decoded selected pair of code words having a time interval below said predetermined value, a first signal for controlling a device, and f. generating, in response to a decoded seleCted pair of code words having a time interval above said perdetermined value, a second signal dependent on said time interval for automatically tuning a second channel in said receiver to said local frequency to receive said selected messages following code words pairs having time intervals above said predetermined value.
-
2. second detecting means controlled by said first detecting means for detecting the modulating binary code word,
-
3. the time interval between the code words in each pair being above or below a predetermined value, b. transmitting from said first station, on a local frequency determined by the length of said time interval, selected messages following code word pairs having time intervals above said predetermined value, code word pairs having time intervals below said predetermined value uniquely specifying a relatively brief message or command, c. receiving at said second station said single carrier frequency with a receiver having a first channel permanently tuned to said single carrier frequency, d. decoding selected pairs of the transmitted code words, e. generating, in response to a decoded selected pair of code words having a time interval below said predetermined value, a first signal for controlling a device, and f. generating, in response to a decoded seleCted pair of code words having a time interval above said perdetermined value, a second signal dependent on said time interval for automatically tuning a second channel in said receiver to said local frequency to receive said selected messages following code words pairs having time intervals above said predetermined value.
-
4. A vehicle communication system as defined in claim 3 further comprising a mobile radio transmitter associated with said mobile receiver and responsive to one of said unique pairs of spaced code words to transmit a message.
-
5. a source of long duration message signals, and
-
6. A communication system as defined in claim 4 wherein said message is transmitted on said first carrier frequency.
-
7. automatic channel tuning means responsive to said second output signal for automatically tuning said second channel to said second carrier frequency to receive said long duration message signal, and
-
8. A vehicle communication system as defined in claim 4 wherein said message is transmitted on another local frequency determined by the time interval of a detected code word pair, and further comprising a central receiver associated with said central transmitter for receiviNg the transmitted message on said other local frequency.
-
9. A vehicle communication system as defined in claim 3 wherein said mobile receiver is located in a vehicle, and further comprising a. a mobile transmitter in said vehicle for transmitting a single code word on another carrier frequency;
- b. a remote transponder for receiving and retransmitting said single code word;
c. a third channel in said mobile receiver and tuned to said other carrier frequency for receiving the retransmitted code word; and
d. timing means for generating a timing signal indicative of the time interval between the transmission of said single code word and the reception of the said single code word retransmitted by said transponder.
- b. a remote transponder for receiving and retransmitting said single code word;
-
10. A vehicle communication system as defined in claim 9 wherein said first carrier frequency and said other carrier frequency are identical and said transponder is located in another vehicle so that said timing signal is indicative of the spacing between the two vehicles.
-
11. A vehicle communication system as defined in claim 3 wherein said binary code words are chosen from the class of linear maximal binary sequences and linear non-maximal preferred polynomial sequences and said decoding means comprises a digital matched filter.
-
12. A vehicle communication system as defined in claim 11 further comprising:
- a. a mobile radio transmitter associated with said mobile radio receiver and responsive to a single code word from said central radio transmitter to retransmit said single code word;
b. a central radio receiver associated with said central transmitter for receiving the retransmitted single code word; and
c. timing means in said central receiver for measuring the time interval between the transmission of said single code word and the reception of the said retransmitted single code word.
- a. a mobile radio transmitter associated with said mobile radio receiver and responsive to a single code word from said central radio transmitter to retransmit said single code word;
-
13. A vehicle communication system as defined in claim 3 wherein said central radio transmitter and said mobile receiver are located in different vehicles.
-
14. A vehicle communication system as defined in claim 3 wherein the messages and commands transmitted between said at least one central station and one or more of a plurality of mobile stations are divided into optional and non-optional categories, said decoding means in said receiver being divided into a plurality of channels designated either as optional or non-optional, said receiver further comprising:
- a. optional information request means for activating selected optional channels in said decoding means, and b. automatic reset means responsive to the second of the pair of code words decoded by said decoding means corresponding to a selected optional channel for deactivating that channel.
-
15. A vehicle communication system as defined in claim 14 wherein said receiver further comprises manual inhibiting means for inhibiting a selected one of said non-optional channels for a predetermined period of time.
-
16. A vehicle communication system as defined in claim 15 wherein said binary code words are chosen from the class of linear maximal binary sequences and linear non-maximal preferred polynomial sequences and each of said plurality of channels in said decoding means comprises a digital matched filter.
-
17. A vehicle communication system as defined in claim 3 wherein said source of long duration message signals comprises:
- a. storage means for storing said long duration message, and b. means for repetitively reading said long duration message out of said storage means to said second means for modulation under the control of said time interval generating means.
-
18. In a vehicle communication system for transmitting messages and commands between at least one central station and one or more of a plurality of mobile stations, said communication system including a central radio transmitter having means for generating a plurality of unique binary code words each specifying a different communication function, time interval generating means for controlling said codE word generating means to generate a repetitive sequence of identical pairs, the time interval between the code words in each pair being above or below a predetermined value, means for selecting one of said unique binary code words for transmission, first means for modulating a first carrier frequency signal with the repetitive sequence of pairs of the selected code word, a source of long duration message signals, and second means for modulating a second carrier frequency signal with said long duration message signals between the transmission of pairs of the selected code words, a mobile receiver comprising:
- a. a first channel permanently tuned to said first carrier frequency and a second tunable channel, b. first detecting means for detecting when said first carrier frequency signal exceeds a predetermined threshold, c. second detecting means controlled by said first detecting means for detecting the modulating binary code word, d. decoding means for decoding selected pairs of code words detected by said second detecting means, e. means connected to the output of said decoding means for measuring the time interval between each pair of decoded binary code words, f. switching matrix means connected to the outputs of said decoding means and said time interval measuring means for generating a first set of output signals if the time interval between code word pairs is below said predetermined value, and a second output signal if the time interval between code word pairs is above said predetermined value, g. output means responsive to said first set of output signals for providing a message or command output, h. automatic channel tuning means responsive to said second output signal for automatically tuning said second channel to said second carrier frequency to receive said long duration message signal, and i. means for detecting the cessation of said second carrier frequency signal for retuning said second channel to its original frequency at the end of said long duration message signal.
Specification