Transmitter control apparatus

• US 4,013,959 A
• Filed: 03/05/1976
• Issued: 03/22/1977
• Est. Priority Date: 03/05/1976
• Status: Expired due to Term

• Current Assignee: Ericsson GE Mobile Communications Inc (Telefonaktiebolaget LM Ericsson)
• Original Assignee: General Electric Company
• Inventors: Patterson, Hubert A.
• Primary Examiner(s): Griffin, Robert L.
• Assistant Examiner(s): Bookbinder, Marc E.
• Application Number:
  US05/664,084
• Time in Patent Office: 382 Days
• Field of Search: 325/101, 325/51, 325/57, 325/158, 325/161, 325/164, 325/166, 325/183, 325/187, 325/55, 178/58 R, 178/58 A, 343/177, 343/207, 343/208, 179/2 CA, 179/2 AM, 340/150, 340/151, 340/152 R, 340/152 T, 340/295, 340/311, 340/312, 340/147 LP, 340/346, 340/217, 340/287
• US Class Current: 455/528
• CPC Class Codes: H04B 1/04 Circuits

Abstract

A plurality of transmitters, such as radio transmitters, frequently share a common communication medium or path, such as a single radio frequency channel. In order to prevent two transmitters from simultaneously transmitting over the common medium, each transmitter is provided with control apparatus. This apparatus causes transmission in response to a start action and in the absence of any other transmission on the medium. The apparatus also produces a repeating signal at predetermined intervals in response to the start action, so that if there is a transmission on the medium, the repeating signal continues until such time as there is an absence of any transmission on the medium. The repeating signal then causes a transmission, and thereafter the repeating signal is stopped. The interval between repeating signals may be the same for each transmitter, but simultaneous transmission by two transmitters will not or is very unlikely to occur because start times are likely to be different.

Claims

1. Apparatus for controlling the transmission of stored data or information from at least one of a plurality of radio transmitters or the like over a common medium comprising:

a. first gating means having first and second inputs and an output;

b. second gating means having first and second inputs and an output;

c. start signal producing means;

d. a repeating device having a start input connected to said start signal producing means and having an output at which a signal is repetitively produced at predetermined intervals in response to a start signal applied to said start input;

e. means responsive to the absence of transmission on said common medium for producing a first signal;

f. means connecting said inputs of said first gating means to said start signal producing means and to said medium responsive means for causing said first gating means to produce a first transmit signal in response to said start signal and said first signal occurring at the same time;

g. means connecting said inputs of said second gating means to said repeating device output and to said medium responsive means for causing said second gating means to produce a second transmit signal in response to said repetitive signal and said first signal occurring at the same time;

h. and means for connecting said first and second gating means outputs to said one transmitter so as to cause transmission in response to one of said transmit signals.

2. The apparatus of claim 1 wherein said repeating device has a reset input for resetting said repeating device in response to said transmission.

3. Apparatus for controlling an information transmitter sharing a common medium with at least one other information transmitter so as to prevent simultaneous transmission by a plurality of transmitters over said medium, said apparatus comprising:

a. means for producing a start signal;

b. means for producing a first transmit signal in response to said start signal and the absence of any other transmission on said medium;

c. means for producing repeating signals in response to said start signal;

d. means for producing a second transmit signal in response to one of said repeating signals and the absence of any other transmission on said medium;

e. and means to cause said controlled transmitter to transmit said information in response to one of said transmit signals.

4. The apparatus of claim 3, and further comprising means connected to said repeating signal producing means for stopping said repeating signals in response to the transmission of said controlled transmitter.

5. Apparatus for controlling an information transmitter sharing a common medium with at least one other information transmitter so as to prevent simultaneous transmission by a plurality of transmitters over said medium, said apparatus comprising:

a. input means for receiving a start signal;

b. first means for producing a first transmit signal in response to said start signal and the absence of any other transmission on said medium;

c. second means for producing repeating signals in response to said start signal;

d. third means for producing a second transmit signal in response to one of said repeating signals and the absence of any other transmission on said medium;

e. and output means connected to said first and third means for causing said controlled transmitter to transmit said information in response to one of said first and second transmit signals.

6. The apparatus of claim 5, and further comprising means connected to said repeating signal producing means for stopping said repeating signals in response to the transmission of said controlled transmitter.