Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
217 words
A radio interference detection device for use in a multi-channel access angle-modulation radio system including at least one stationary station and at least one mobile station, said device comprising: detecting means for AM-detecting a reception signal prior to angle demodulation and for producing an AM component of the reception signal; rectifying means for rectifying an output signal from said detecting means; and determining means for determining a level of an output signal from said rectifying means and for detecting interference in accordance with a determination result, said determining means comprising: angle demodulating means for angle-demodulating the reception signal; first converting means for converting a first band component of the output from said angle demodulating means to a first DC signal; second converting means for converting a second band component other than the first component of the output from said angle demodulating means to a second DC signal; a comparator for producing a detection signal when the level of the output signal from said rectifying means exceeds a first predetermined level; and a gate connected to an output end of said comparator, said gate being enabled to pass an output signal from said comparator when one of the levels of the first and second DC signals from said first and second converting means exceeds a second predetermined level.
Claim 2
Dependent Claim
217 words
A radio interference detection device for use in a multi-channel access angle-modulation radio system including at least one stationary station and at least one mobile station, said device comprising: detecting means for AM-detecting a reception signal prior to angle demodulation and for producing an AM component of the reception signal; rectifying means for rectifying an output signal from said detecting means; and determining means for determining a level of an output signal from said rectifying means and for detecting interference in accordance with a determination result, said determining means comprising: angle demodulating means for angle-demodulating the reception signal; first converting means for converting a first band component of the output from said angle demodulating means to a first DC signal; second converting means for converting a second band component other than the first component of the output from said angle demodulating means to a second DC signal; a comparator for producing a detection signal when the level of the output signal from said rectifying means exceeds a first predetermined level; and a gate connected to an output end of said comparator, said gate being enabled to pass an output signal from said comparator when one of the levels of the first and second DC signals from said first and second converting means exceeds a second predetermined level.
Claim 3
Dependent Claim
29 words
A device according to claim 1, in which said first and second converting means respectively include a low-pass filter and a high-pass filter which have the same cutoff frequency.
Claim 4
Dependent Claim
75 words
A device according to claim 1, in which said gate comprises an AND gate, the first and second DC signals from said first and second converting means being supplied to noninverting input ends of first and second comparators, respectively, a signal having the second predetermined level, being supplied to inverting input ends of the first and second comparator, and said first and second comparators supplying output signals to said AND gate through a NAND gate.
Claim 5
Dependent Claim
189 words
A radio interference detection device for use in a multi-channel access angle-modulation radio system including at least one stationary station and at least one mobile station, said device comprising: detecting means for AM-detecting a reception signal prior to angle demodulation and for producing an AM component of the reception signal; rectifying means for rectifying an output signal from said detecting means; and determining means for determining a level of an output signal from said rectifying means and for detecting interference in accordance with a determination result, said determining means comprising: angle demodulating means for angle-demodulating the reception signal; a first comparator for comparing a DC level of an output signal from said angle demodulating means and a level of the output signal from said rectifying means; a second comparator for producing a detection signal when the level of the output signal from said rectifying means exceeds a predetermined level; and a gate for passing said detecting signal from said second comparator only when said first comparator produces a signal indicating that a demodulated output from said angle demodulating means is smaller than the output signal from said rectifying means.
Claim 6
Dependent Claim
189 words
A radio interference detection device for use in a multi-channel access angle-modulation radio system including at least one stationary station and at least one mobile station, said device comprising: detecting means for AM-detecting a reception signal prior to angle demodulation and for producing an AM component of the reception signal; rectifying means for rectifying an output signal from said detecting means; and determining means for determining a level of an output signal from said rectifying means and for detecting interference in accordance with a determination result, said determining means comprising: angle demodulating means for angle-demodulating the reception signal; a first comparator for comparing a DC level of an output signal from said angle demodulating means and a level of the output signal from said rectifying means; a second comparator for producing a detection signal when the level of the output signal from said rectifying means exceeds a predetermined level; and a gate for passing said detecting signal from said second comparator only when said first comparator produces a signal indicating that a demodulated output from said angle demodulating means is smaller than the output signal from said rectifying means.
Claim 7
Dependent Claim
83 words
A device according to claim 4, in which said gate comprises an AND gate which receives the output signals from said first and second comparators, said first comparator having noninverting and inverting input ends to which the output signal from said rectifying means and the DC component of the angle-demodulated signal are respectively supplied, and said second comparator having noninverting and inverting input ends to which the output signal from said rectifying means and the signal having a predetermined level are respectively supplied.