US 5,353,304 A · Surface acoustic wave device, and demodulating apparatus and communication system using the surface acoustic wave device

A surface acoustic wave device, said device comprising:

a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with an input signal, said input electrode being formed on said substrate;
and
an output electrode for converting the surface acoustic wave to an electric signal, said output electrode being formed on said substrate;
and
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave and satisfies an equation L+.DELTA.l=2V/A where L is a length of one of said input and output electrodes in the propagation direction, .DELTA.l is a length of a space between said taps, A is a transmission speed of the input signal and V is a propagation velocity of the surface acoustic wave.

3 more elements

A demodulating device comprising:

(a) a surface acoustic wave device for supplying a correlation signal based on an input signal modulated in accordance with data, said surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with an input signal, said input electrode being formed on said substrate;
and
an output electrode for converting the surface acoustic wave to an electric signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave and satisfies an equation L+.DELTA.l=2V/A where L is a length of one of said input and output electrodes in the propagation direction, .DELTA.l is a length of a space between said taps, A is a transmission speed of the input signal and V is a propagation velocity of the surface acoustic wave;
(b) a detection circuit for envelope-detecting the correlation signal supplied from said surface acoustic wave device to supply an output;
and
(c) a data judging circuit for judging the data based on the output from said detection circuit.

6 more elements

A demodulating device comprising:

(a) a surface acoustic wave device for supplying a correlation signal based on an input signal modulated in accordance with data, said surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with an input signal, said input electrode being formed on said substrate;
and
an output electrode for converting the surface acoustic wave to an electric signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises first and second electrodes which are arranged along a direction perpendicular to a propagation direction of the surface acoustic wave, said first and second electrodes respectively comprise a 2N number of taps (N is a natural number) which are equidistantly arranged in the propagation direction of the surface acoustic wave, said first electrode is structured so that a signal polarity corresponding to the tap, which is the i-th one (i=1, 2, . . . , N) counted from one side, is the same as a signal polarity corresponding to the (N+i)-th tap counted from the same side, said second electrode is structured so that a signal polarity corresponding to the tap, which is the i-th one (i=1, 2, . . . , N) counted from one side, is opposite to a signal polarity corresponding to the (N+i)-th tap counted from the same side, and said first and second electrodes respectively satisfy an equation L+.DELTA.l=2V/A where L is a length of each of said first and second electrodes in the propagation direction, .DELTA.l is a length of a space between said taps, A is a transmission speed of the input signal and V is a propagation velocity of the surface acoustic wave;
(b) a detection circuit for envelope-detecting the correlation signal supplied from said surface acoustic wave device to supply an output;
and
(c) a data judging circuit for judging the data based on the output from said detection circuit.

6 more elements

A communication system comprising:

(a) a transmitter for transmitting a signal modulated in accordance with data;
(b) a receiver circuit for receiving the signal transmitted from said transmitter;
(c) a surface acoustic wave device for supplying a correlation signal based on the signal received by said receiver circuit, said surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with the received signal, said input electrode being formed on said substrate;
and
an output electrode for receiving the surface acoustic wave and supplying the correlation signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave and satisfies an equation L+.DELTA.l=2V/A where L is a length of one of said input and output electrodes in the propagation direction, .DELTA.l is a length of a space between said taps, A is a transmission speed of the input signal and V is a propagation velocity of the surface acoustic wave;
(d) a detection circuit for envelope-detecting the correlation signal supplied from said surface acoustic wave device to supply an output;
and
(e) a data judging circuit for judging the data based on the output from said detection circuit.

8 more elements

A communication system comprising:

(a) a transmitter for transmitting a signal modulated in accordance with data;
(b) a receiver circuit for receiving the signal transmitted from said transmitter;
(c) a surface acoustic wave device for supplying a correlation signal based on the signal received by said receiver circuit, said surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with the received signal, said input electrode being formed on said substrate;
and
an output electrode for receiving the surface acoustic wave and supplying the correlation signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises first and second electrodes which are arranged along a direction perpendicular to a propagation direction of the surface acoustic wave, said first and second electrodes respectively comprise a 2N number of taps (N is a natural number) which are equidistantly arranged in the propagation direction of the surface acoustic wave, said first electrode is structured so that a signal polarity corresponding to the tap, which is the i-th one (i=1, 2, . . . , N) counted from one side, is the same as a signal polarity corresponding to the (N+i)-th tap counted from the same side, said second electrode is structured so that a signal polarity corresponding to the tap, which is the i-th one (i=1, 2, . . . , N) counted from one side, is opposite to a signal polarity corresponding to the (N+i)-th tap counted from the same side, and said first and second electrodes respectively satisfy an equation L+.DELTA.l=2V/A where L is a length of each of said first and second electrodes in the propagation direction, .DELTA.l is a length of a space between said taps, A is a transmission speed of the input signal and V is a propagation velocity of the surface acoustic wave;
(d) a detection circuit for envelope-detecting the correlation signal supplied from said surface acoustic wave device to supply an output;
and
(e) a data judging circuit for judging the data based on the output from said detection circuit.

8 more elements

A demodulating device comprising:

(a) a branching device for dividing a signal modulated in accordance with data into first and second input signals;
(b) a first surface acoustic wave device for supplying a first correlation signal based on the first input signal divided by said branching device, said first surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with the input signal, said input electrode being formed on said substrate;
and
an output electrode for receiving the surface acoustic wave and supplying the correlation signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave, is structured so that a signal polarity corresponding to the tap, which is the i-th one (i=1, 2, . . . , N) counted from one side, is the same as a signal polarity corresponding to the (N+i)-th tap counted from the same side, and satisfies an equation L+.DELTA.l=2V/A where L is a length of one of said input and output electrodes in the propagation direction, .DELTA.l is a length of a space between said taps, A is a transmission speed of the input signal and V is a propagation velocity of the surface acoustic wave;
(c) a second surface acoustic wave device for supplying a second correlation signal based on the second input signal divided by said branching device, said second surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with the input signal, said input electrode being formed on said substrate;
and
an output electrode for receiving the surface acoustic wave and supplying the correlation signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave, is structured so that a signal polarity corresponding to the tap, which is the i-th one (i=1, 2, . . . , N) counted from one side, is opposite to a signal polarity corresponding to the (N+i)-th tap counted from the same side, and satisfies an equation L+.DELTA.l=2V/A where L is a length of one of said input and output electrodes in the propagation direction, .DELTA.l is a length of a space between said taps, A is a transmission speed of the input signal and V is a propagation velocity of the surface acoustic wave;
(d) a first detection circuit for envelope-detecting the first correlation signal supplied from said first surface acoustic wave device to supply an output;
and
(e) a second detection circuit for envelope-detecting the second correlation signal supplied from said second surface acoustic wave device to supply an output;
and
(f) a comparator circuit for comparing the outputs supplied from said first and second detection circuits.

15 more elements

A communication system comprising:

(a) a transmitter for transmitting a signal modulated in accordance with data;
(b) a receiver circuit for receiving the signal transmitted from said transmitter;
(c) a branching device for dividing the signal received by said receiver circuit into first and second input signals;
(d) a first surface acoustic wave device for supplying a first correlation signal based on the first input signal divided by said branching device, said first surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with the input signal, said input electrode being formed on said substrate;
and
an output electrode for receiving the surface acoustic wave and supplying the correlation signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a 2N number of taps (n is a natural number) equidistantly arranged in a propagation direction of the surface acoustic wave, is structured so that a signal polarity corresponding to the tap, which is the i-th one (i=1, 2, . . . , N) counted from one side, is the same as a signal polarity corresponding to the (N+i)-th tap counted from the same side, and satisfies an equation L+.DELTA.l=2V/A where L is a length of one of said input and output electrodes in the propagation direction, .DELTA.l is a length of a space between said taps, A is a transmission speed of the input signal and V is a propagation velocity of the surface acoustic wave;
(e) a second surface acoustic wave device for supplying a second correlation signal based on the second input signal divided by said branching device, said second surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with the input signal, said input electrode being formed on said substrate;
and
an output electrode for receiving the surface acoustic wave and supplying the correlation signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave, is structured so that a signal polarity corresponding to the tap, which is the i-th one (i=1, 2, . . . , N) counted from one side, is opposite to a signal polarity corresponding to the (N+i)-th tap counted from the same side, and satisfies an equation L+.DELTA.l=2V/A where L is a length of one of said input and output electrodes in the propagation direction, .DELTA.l is a length of a space between said taps, A is a transmission speed of the input signal and V is a propagation velocity of the surface acoustic wave;
(e) a first detection circuit for envelope-detecting the first correlation signal supplied from said first surface acoustic wave device to supply an output;
and
(f) a second detection circuit for envelope-detecting the second correlation signal supplied from said second surface acoustic wave device to supply an output;
and
(g) a comparator circuit for comparing the outputs supplied from said first and second detection circuits.

17 more elements

A demodulating device comprising:

(a) a surface acoustic wave device for supplying a correlation signal based on an input signal modulated in accordance with data, said surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with an input signal, said input electrode being formed on said substrate;
and
an output electrode for receiving the surface acoustic wave and supplying the correlation signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave, the other one of said input and output electrodes comprises first and second taps arranged at a predetermined distance in the propagation direction, and said the other electrode satisfies an equation D=nV/A where D is a distance between center lines of said first and second taps in the propagation direction, A is a transmission speed of the input signal, V is a propagation velocity of the surface acoustic wave and n is a positive integer;
(b) a detection circuit for envelope-detecting the correlation signal supplied from said surface acoustic wave device to supply an output;
and
(c) a data judging circuit for judging the data based on the output from said detection circuit.

6 more elements

A demodulating device comprising:

(a) a surface acoustic wave device for supplying a correlation signal based on an input signal modulated in accordance with data, said surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with an input signal, said input electrode being formed on said substrate;
and
an output electrode for receiving the surface acoustic wave and supplying the correlation signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave, the other one of said input and output electrodes comprises first and second electrodes arranged in a direction perpendicular to the propagation direction, said first electrode comprises first and second taps arranged at a predetermined distance in the propagation direction, said second electrode comprises third and fourth taps arranged at a predetermined distance in the propagation diraction, and said first and second electrodes respectively satisfy an equation D=nV/A where D is a distance between center lines of said first and second taps in the propagation direction, A is a transmission speed of the input signal, V is a propagation velocity of the surface acoustic wave and n is a positive integer;
(b) a detection circuit for envelope-detecting the correlation signal supplied from said surface acoustic wave device to supply an output;
and
(c) a data judging circuit for judging the data based on the output from said detection circuit.

6 more elements

A communication system comprising:

(a) a transmitter for transmitting a signal modulated in accordance with data;
(b) a receiver circuit for receiving the signal transmitted from said transmitter;
(c) a surface acoustic wave device for supplying a correlation signal based on the signal received by said receiver circuit, said surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with the received signal, said input electrode being formed on said substrate;
and
an output electrode for receiving the surface acoustic wave and supplying the correlation signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave, the other one of said input and output electrodes comprises first and second taps arranged at a predetermined distance in the propagation direction, and said the other electrode satisfies an equation D=nV/A where D is a distance between center lines of said first and second taps in the propagation direction, A is a transmission speed of the input signal, V is a propagation velocity of the surface acoustic wave and n is a positive integer;
(d) a detection circuit for envelope-detecting the correlation signal supplied from said surface acoustic wave device to supply an output;
and
(e) a data judging circuit for judging the data based on the output from said detection circuit.

8 more elements

A communication system comprising:

(a) a transmitter for transmitting a signal modulated in accordance with data;
(b) a receiver circuit for receiving the signal transmitted from said transmitter;
(c) a surface acoustic wave device for supplying a correlation signal based on the signal received by said receiver circuit, said surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with the received signal, said input electrode being formed on said substrate;
and
an output electrode for receiving the surface acoustic wave and supplying the correlation signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave, the other one of said input and output electrodes comprises first and second electrodes arranged in a direction perpendicular to the propagation direction, said first electrode comprises first and second taps arranged at a predetermined distance in the propagation direction, said second electrode comprises third and fourth taps arranged at a predetermined distance in the propagation diraction, and said first and second electrodes respectively satisfy an equation D=nV/A where D is a distance between center lines of said first and second taps in the propagation direction, A is a transmission speed of the input signal, V is a propagation velocity of the surface acoustic wave and n is a positive integer;
(d) a detection circuit for envelope-detecting the correlation signal supplied from said surface acoustic wave device to supply an output;
and
(e) a data judging circuit for judging the data based on the output from said detection circuit.

8 more elements

A demodulating device comprising:

(a) a branching device for dividing a signal modulated in accordance with data into first and second input signals;
(b) a first surface acoustic wave device for supplying a first correlation signal based on the first input signal divided by said branching device, said first surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with the input signal, said input electrode being formed on said substrate;
and
an output electrode for converting the surface acoustic wave to an electric signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave, the other one of said input and output electrodes comprises first and second taps arranged at a predetermined distance in the propagation direction, a signal polarity corresponding to said first tap is the same as a signal polarity corresponding to said second tap, and said the other electrode satisfies an equation D=nV/A where D is a distance between center lines of said first and second taps in the propagation direction, A is a transmission speed of the input signal, V is a propagation velocity of the surface acoustic wave and n is a positive integer;
(c) a second surface acoustic wave device for supplying a second correlation signal based on the second input signal divided by said branching device, said second surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with the input signal, said input electrode being formed on said substrate;
and
an output electrode for converting the surface acoustic wave to an electric signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave, the other one of said input and output electrodes comprises third and fourth taps arranged at a predetermined distance in the propagation direction, a signal polarity corresponding to said third tap is opposite to a signal polarity corresponding to said fourth tap, and said the other electrode satisfies an equation D=nV/A where D is a distance between center lines of said third and fourth taps in the propagation direction, A is a transmission speed of the input signal, V is a propagation velocity of the surface acoustic wave and n is a positive integer;
(d) a first detection circuit for envelope-detecting the first correlation signal supplied from said first surface acoustic wave device to supply an output;
and
(e) a second detection circuit for envelope-detecting the second correlation signal supplied from said second surface acoustic wave device to supply an output;
and
(f) a comparator circuit for comparing the outputs supplied from said first and second detection circuits.

15 more elements

A communication system comprising:

(a) a transmitter for transmitting a signal modulated in accordance with data;
(b) a receiver circuit for receiving the signal transmitted from said transmitter;
(c) a branching device for dividing the signal received by said receiver circuit into first and second input signals;
(d) a first surface acoustic wave device for supplying a first correlation signal based on the first input signal divided by said branching device, said first surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with the input signal, said input electrode being formed on said substrate;
and
an output electrode for converting the surface acoustic wave to an electric signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave, the other one of said input and output electrodes comprises first and second taps arranged at a predetermined distance in the propagation direction, a signal polarity corresponding to said first tap is the same as a signal polarity corresponding to said second tap and said the other electrode satisfies an equation D=nV/A where D is a distance between center lines of said first and second taps in the propagation direction, A is a transmission speed of the input signal, V is a propagation velocity of the surface acoustic wave and n is a positive integer;
(e) a second surface acoustic wave device for supplying a second correlation signal based on the second input signal divided by said branching device, said second surface acoustic wave device comprising:
a piezoelectric substrate;
an input electrode for generating a surface acoustic wave propagated in a predetermined direction, in accordance with the input signal, said input electrode being formed on said substrate;
and
an output electrode for converting the surface acoustic wave to an electric signal, said output electrode being formed on said substrate;
wherein one of said input and output electrodes comprises a plurality of taps equidistantly arranged in a propagation direction of the surface acoustic wave, the other one of said input and output electrodes comprises third and fourth taps arranged at a predetermined distance in the propagation direction, a signal polarity corresponding to said third tap is opposite to a signal polarity corresponding to said fourth tap and said the other electrode satisfies an equation D=nV/A where D is a distance between center lines of said third and fourth taps in the propagation direction, A is a transmission speed of the input signal, V is a propagation velocity of the surface acoustic wave and n is a positive integer;
(e) a first detection circuit for envelope-detecting the first correlation signal supplied from said first surface acoustic wave device to supply an output;
and
(f) a second detection circuit for envelope-detecting the second correlation signal supplied from said second surface acoustic wave device to supply an output;
and
(g) a comparator circuit for comparing the outputs supplied from said first and second detection circuits.

17 more elements

Surface acoustic wave device, and demodulating apparatus and communication system using the surface acoustic wave device

Life of this patent

Surface acoustic wave device, and demodulating apparatus and communication system using the surface acoustic wave device

Life of this patent

Abstract

Claims70