Method for the transmission of binary information by means of a frequency-modulated signal and a circuit for performing that method

Claim 3

A method as claimed in claim 1, wherein the first number a 1 and the fourth number a 2 are both substantially equal to a, and the second number b 1 and the third number b 2 are both substantially equal to b, where b is unequal to a.

Claim 4

A method as claimed in claim 2 wherein one of the time durations a and b is substantially twice as large as the other.

Claim 5

A circuit for transmitting binary information by means of a frequency-modulated signal, said circuit comprising means for transmitting one of the possible binary information units with a frequency-modulated signal which during a given first time duration extending for a first number of periods a 1 always continuously has a first frequency f 1 and which immediately thereafter during a given second time duration extending for a second number of periods b 1 always continuously has a frequency f 2 , and means for immediately thereafter transmitting said one possible binary information unit or the other possible binary information unit with a frequency-modulated signal which first always continuously has during a third time duration extending for a third number of b 2 periods the first frequency f 1 and immediately thereafter during a fourth time duration extending for a fourth number of a 2 periods always continously has the second frequency f 2 , wherein (a 1 - b 1 ) is unequal to (b 2 - a 2 ).

Claim 6

A circuit for transmitting binary information by means of a frequency-modulated signal, said circuit comprising means for transmitting one of the possible binary information units with a frequency-modulated signal which during a given first time duration extending for a first number of periods a 1 always continuously has a first frequency f 1 and which immediately thereafter during a given second time duration extending for a second number of periods b 1 always continuously has a frequency f 2 , and means for immediately thereafter transmitting said one possible binary information unit or the other possible binary information unit with a frequency-modulated signal which first always continuously has during a third time duration extending for a third number of b 2 periods the first frequency f 1 and immediately thereafter during a fourth time duration extending for a fourth number of a 2 periods always continously has the second frequency f 2 , wherein (a 1 - b 1 ) is unequal to (b 2 - a 2 ).

Claim 7

A circuit as claimed in claim 4, wherein the first number a 1 and the fourth number a 2 are both substantially equal to a, and the second number b 1 and the third number b 2 are both substantially equal to b where b is unequal to a.

Claim 8

A circuit as claimed in claim 5, wherein one of the time durations extending for a number of periods a and b is substantially twice as large as the other.

Claim 9

A circuit as claimed in claim 4, wherein both of said transmitting means together comprise a frequency converter device having an output, a control circuit means for operating said converting device, said control circuit including an input means for receiving the binary information i to be transmitted, and a plurality of further inputs, and a counting circuit having a plurality of output means coupled to said further inputs respectively and providing a, b, and (a+b) signals respectively, and a counting input coupled to said output of the frequency converter device.

Claim 10

A circuit as claimed in claim 7, wherein the control circuit comprises a bistable trigger circuit having a setting and resetting inputs and an output, a gate circuit means for supplying a signal equal to ai' + bi to the resetting input, the output of the control circuit being coupled with said output of the trigger circuit.

Claim 11

A remote control system comprising a circuit as claimed in claim 4.

Claim 12

A remote control system as claimed in claim 9, comprising an ultra-sound transmission system.

Claim 13

A circuit for receiving binary information transmitted as a frequency-modulated signal, wherein one of the possible binary information units is transmitted as a frequency-modulated signal which during a given first time duration extending for a first number of periods a 1 has a first frequency f 1 and which thereafter during a given second time duration extending for a second number of periods b 1 has a frequency f 2 and the other possible binary information unit is transmitted as a frequency modulated signal which first has during a third dime duration extending for a third number of b 2 periods the first frequency f 1 and thereafter during a fourth time duration extending for a fourth number of a 2 periods the second frequency f 2 , wherein (a 1 - b 2 ) is unequal to (b 2 - a 2 ), said circuit comprising a frequency separating circuit having input means for receiving said transmitted signal and a pair of output means for respectively obtaining signals of the first frequency f 1 and the secondy frequency f 2 from said transmitted signal, a counting and comparison circuit having a pair of inputs coupled to said output means respectively, a resetting input, and an output means for supplying the transmitted binary information, and a detection circuit means coupled with at least one of the said outputs of the frequency separating circuit for detecting a change in the occurrence of a signal of the second frequency to the occurrence of a signal of the first frequency, said resetting input of the counting and comparison circuit being coupled with an output of this detection circuit.

Claim 14

A circuit for receiving binary information transmitted as a frequency-modulated signal, wherein one of the possible binary information units is transmitted as a frequency-modulated signal which during a given first time duration extending for a first number of periods a 1 has a first frequency f 1 and which thereafter during a given second time duration extending for a second number of periods b 1 has a frequency f 2 and the other possible binary information unit is transmitted as a frequency modulated signal which first has during a third dime duration extending for a third number of b 2 periods the first frequency f 1 and thereafter during a fourth time duration extending for a fourth number of a 2 periods the second frequency f 2 , wherein (a 1 - b 2 ) is unequal to (b 2 - a 2 ), said circuit comprising a frequency separating circuit having input means for receiving said transmitted signal and a pair of output means for respectively obtaining signals of the first frequency f 1 and the secondy frequency f 2 from said transmitted signal, a counting and comparison circuit having a pair of inputs coupled to said output means respectively, a resetting input, and an output means for supplying the transmitted binary information, and a detection circuit means coupled with at least one of the said outputs of the frequency separating circuit for detecting a change in the occurrence of a signal of the second frequency to the occurrence of a signal of the first frequency, said resetting input of the counting and comparison circuit being coupled with an output of this detection circuit.

Claim 15

A circuit as claimed in claim 11, wherein the detection circuit comprises a counter having a counting input and an output, a change-over device coupled between said counter and said separating circuit, said change over device having a control signal input, a two-scaler having an output coupled to said control signal input and an input coupled to said output of the counter of the detection circuit, the resetting input of the counting and comparison circuit being coupled to an output of the two-scaler.

Claim 16

A circuit as claimed in claim 12, wherein the frequency separating circuit includes a further output means for supplying signals of another than the first and the second frequency, the counter of the detection circuit having a down-counting input, and further comprising a further change-over device coupled between said further output means and said down counting input and having a control signal input coupled to an output of the two-scaler.

Claim 17

A circuit as claimed in claim 11, wherein the counting and comparison circuit comprises a two-way counter having a sign output means for supplying the transmitted binary information.