Transmitter modulated with three modulation patterns

• US 4,103,238 A
• Filed: 11/26/1976
• Issued: 07/25/1978
• Est. Priority Date: 11/26/1976
• Status: Expired due to Term

• Current Assignee: GMI Holdings Incorporated (Sanwa Holdings Corp.)
• Original Assignee: Alliance Manufacturing Co Inc (Koninklijke Philips N.V.)
• Inventors: Deming, Andrew F., Russell, James B.
• Primary Examiner(s): Griffin, Robert L.
• Assistant Examiner(s): Ng, Jin F.
• Application Number:
  US05/744,976
• Time in Patent Office: 606 Days
• Field of Search: 325/37, 325/39, 325/40, 325/55, 325/64, 325/141, 325/143, 325/183, 325/139, 340/167 R, 340/171 R, 340/171 A, 340/171 PF, 340/348, 340/349, 340/351, 340/365 R, 340/365 S, 343/225-227, 179/15 BA, 179/15 AN, 179/84 SS
• US Class Current: 375/306
• CPC Class Codes: H04B 2001/0491 with frequency synthesizers, frequency converters or modulators
• CPC Class Codes: H04L 25/4904 using self-synchronising codes, e.g. split-phase codes
• CPC Class Codes: H04L 7/065 and superimposed by modulation

Abstract

An encoding transmitter is disclosed which includes a modulator providing a means to modulate a carrier wave selectively with a first or a second modulation frequency or pattern to provide first and second modulation patterns respectively. Also a third modulation pattern may be established by providing successive portions of the first modulation frequency and the second modulation frequency during a given time period. A data selector is controlled by data select control signals which are obtained from a counter counting from the first modulation frequency signal. Programmable means include a multi-position switch to program the input channels of the data selector so as to control whether the first or the third modulation pattern is that which modulates the carrier wave during any given unit of time.

Claims

1. A modulated carrier wave transmitter comprising in combination;

a carrier generator to generate a carrier wave;

means establishing first and second different modulation frequencies;

means establishing time sequential control signals;

modulation means connected to modulate said carrier wave by said first and second modulation frequencies in first, second and third modulation patterns, comprising;

first means connected to modulate said carrier wave with said first modulation frequency in accordance with said sequential control signals to establish said first modulation pattern of said carrier wave for at least one bit period, a bit period being the time period required for the transmission of one complete interval of the first, second or third modulation pattern,

second means connected to modulate said carrier wave with said second modulation frequency in accordance with said sequential control signals to establish said second modulation pattern of said carrier wave for at least one bit period,

and third means connected to modulate said carrier wave with said first modulation frequency and sequentially with said second modulation frequency in accordance with said sequential control signals to establish said third modulation pattern of said carrier wave for at least one bit period, the signal being transmitted containing all three modulation patterns.

2. A transmitter as set forth in claim 1, wherein said modulation frequency establishing means includes an oscillator and a flip-flop connected thereto to establish a square wave first modulation frequency.

3. A transmitter as set forth in claim 1, wherein said control signal establishing means includes a series of dividers to divide the frequency of one of said first and second modulation frequencies.

4. A transmitter as set forth in claim 1, wherein said modulation means includes gating means connected to establish modulation of said carrier wave selectively by said first and second modulation frequencies.

5. A transmitter as set forth in claim 1, wherein said modulation means includes a data selector,

and programmable means connected to said data selector to select the modulation pattern in accordance with said programmable means and said time sequential control signals.

6. A transmitter as set forth in claim 5, wherein said data selector includes a plurality of gates enabled in sequence by said time sequential control signals to establish the modulation of said carrier wave by said first and second modulation frequencies.

7. A transmitter as set forth in claim 6, wherein said programmable means is connected to select one of said first and second modulation frequencies for each unit of time as established by said time sequential control signals.

8. A transmitter as set forth in claim 1, including means to broaden the band width of said carrier wave generator.

9. A transmitter as set forth in claim 8, wherein said band width broadening means includes a circuit operating at a center frequency in the range of said first and second modulation frequencies.

10. A transmitter as set forth in claim 9, wherein said band width broadening means is a circuit resonant to a frequency intermediate said first and second modulation frequencies.

11. A transmitter as set forth in claim 9, wherein said band width broadening means is a circuit resonant to a frequency intermediate said first and second modulation frequencies and closer to said first than to said second frequency.

12. An encoding transmitter comprising in combination;

an encoder having an output and including, oscillator means to generate a first audio frequency signal,

counter means connected to said oscillator to establish a second audio frequency signal, a bit signal and a set of data select control signals,

said second audio frequency signal being 1/x times the frequency of said first audio frequency,

said bit signal being 1/y times the frequency of said second audio frequency,

said set of data select control signals having Z number of output states, wherein X, Y and Z are numerals,

a data selector having a plurality of input channels, one output and control means connected to said data select control signals,

programmable means to program the input channels of said data selector,

a synchronization bit decoder connected to said counter means to decode one count of said Z number of output states,

output selector means connected to said oscillator and to said counter means to select said first and second audio signals on the output of said encoder,

and an output decoder having three input signals one each connected to said counter bit signal, said data selector and said sync bit decoder and having an output connected to said output selector means,

said bit signal comprising a first and a second complementary portion,

and said output decoder establishing first, second and third bit patterns on the output of said encoder with said first bit pattern comprising said first audio signal during both portions of a bit, said second bit pattern comprising said second audio signal during both portions of a bit, and said third bit pattern comprising one of said audio signals during said first portion and the other of said audio signals during said second portion of a bit,

one of said bit patterns being a synchronization bit another being a logic one bit and the third being a logic zero bit,

and a carrier generator modulated by said encoder output.

13. An encoding transmitter as set forth in claim 12, wherein said oscillator includes square wave shaping circuits to establish said first audio frequency signal as a square wave signal.

14. An encoding transmitter as set forth in claim 12, wherein said counter means includes flip-flops to successively divide in half the frequency of said oscillator means.

15. An encoding transmitter as set forth in claim 12, wherein said counter means includes a first divide by 2 divider to establish said second audio frequency, includes a divide by 16 divider to establish said bit signal, and includes dividers establishing 16 output states of said data select control signals.

16. An encoding transmitter as set forth in claim 12, wherein said programmable means includes multiple pole switch means connected to program the input channels of said data selector.

17. An encoding transmitter as set forth in claim 12, wherein said data selector is a Z:

1 multiplexer connected to time division multiplex the signals from said programmable means to the output of said data selector.

18. An encoding transmitter as set forth in claim 12, wherein said synchronization bit decoder is a multiple input gate having inputs from said data select control signals of said counter means to have an output to said output decoder upon decoding said one count of said Z number of output states.

19. An encoding transmitter as set forth in claim 12, wherein said output decoder includes a steering flip-flop connected to be set by said bit signal and overridden by a reset signal from said synchronization bit decoder.

20. An encoding transmitter comprising in combination;

an encoder having an output and including, means to generate a first and a second audio frequency and a bit signal,

said second audio frequency being 1/x times the frequency of said first audio frequency,

said bit signal being 1/y times the frequency of said second audio frequency, wherein X and Y are numerals,

said bit signal comprising first and second complementary portions,

and means including an output decoder connected to said generator means and establishing first, second and third bit patterns on the output of said encoder with said first bit pattern comprising said first audio frequency during both portions of a bit, said second bit pattern comprising said second audio frequency during both portions of a bit, and said third bit pattern comprising one of said audio frequencies during said first portion and the other of said audio frequencies during said second portion of a bit,

one of said bit patterns being a synchronization bit another being a logic one bit and the third being a logic zero bit;

and a carrier generator modulated by said encoder output.

21. A transmitter as set forth in claim 20, including a data selector having a plurality of input channels and an output,

programmable means to program the channels of said data selector,

and means connecting the output of said data selector to said output decoder.

22. A transmitter as set forth in claim 20, wherein said generator means includes counter means connected to receive said first audio frequency and to establish said second audio frequency and said bit signal as divided outputs thereof.

23. A transmitter as set forth in claim 22, wherein said counter means establishes a set of data select control signals,

said set of data select control signals having Z number of output states wherein Z in a numeral,

a data selector having a plurality of input channels, one output and control means connected to said data select control signals,

programmable means to program the input channels of said data selector,

output selector means connected to said generator and said counter means to select said first and second audio signals on the output of said encoder,

and means connecting the output of said output decoder to said output selector means.