Receiver and electronic device
First Claim
1. A receiver which receives a transmitted optical signal as a digital signal constituted by a pulse train with a known pulse width, the receiver comprisingabnormal pulse detection means for detecting, by comparing the received optical signal with a reference digital signal generated based on the optical signal, a variation in pulse width in the optical signal being transmitted, and stopping external output of the received optical signal for a predetermined period of time if the variation in the pulse width is detected in the optical signal, wherein,the optical signal is input as a negative-logic digital signal constituted by a low level indicating a signal “
- 1” and
a high level indicating a signal “
0”
, andthe abnormal pulse detection means includes;
incoming pulse edge detection means for detecting a moment of fall of the received optical signal and outputting a result of detection as an edge detection signal;
reference pulse generation means for generating the reference digital signal as a positive-logic digital signal constituted by a low level indicating a signal “
0” and
a high level indicating a signal “
1”
, based on the edge detection signal output from the incoming pulse edge detection means;
logic means for outputting a signal indicating a negative AND of the optical signal and the reference digital signal;
muting signal generation means for generating, based on a signal generated by logically inverting the signal indicating the negative AND output from the logic means, a muting signal which disallows the external output of the received optical signal for the predetermined period of time; and
output stop means for stopping the external output of the received optical signal for the predetermined period of time, if the muting signal is input.
1 Assignment
0 Petitions
Accused Products
Abstract
An abnormal pulse detection circuit in a receiver of the present invention includes: an incoming pulse edge detection circuit which detects the moment of rise of an input signal and outputs the result of the detection as an edge detection signal; a muting reference pulse generation circuit which generates a muting reference pulse based on the edge detection signal; a logic circuit which outputs a signal indicating a negative AND of the muting reference pulse and the input signal; a muting signal generation circuit which generates a muting signal from the output signal of the logic circuit; and a switching circuit which outputs the input signal or the muting signal. The receiver of the present invention can therefore reduce discomfort in hearing reproduced sound in case where a noise occurs in an audio signal due to a variation in pulse width.
7 Citations
6 Claims
-
1. A receiver which receives a transmitted optical signal as a digital signal constituted by a pulse train with a known pulse width, the receiver comprising
abnormal pulse detection means for detecting, by comparing the received optical signal with a reference digital signal generated based on the optical signal, a variation in pulse width in the optical signal being transmitted, and stopping external output of the received optical signal for a predetermined period of time if the variation in the pulse width is detected in the optical signal, wherein, the optical signal is input as a negative-logic digital signal constituted by a low level indicating a signal “ - 1” and
a high level indicating a signal “
0”
, andthe abnormal pulse detection means includes; incoming pulse edge detection means for detecting a moment of fall of the received optical signal and outputting a result of detection as an edge detection signal; reference pulse generation means for generating the reference digital signal as a positive-logic digital signal constituted by a low level indicating a signal “
0” and
a high level indicating a signal “
1”
, based on the edge detection signal output from the incoming pulse edge detection means;logic means for outputting a signal indicating a negative AND of the optical signal and the reference digital signal; muting signal generation means for generating, based on a signal generated by logically inverting the signal indicating the negative AND output from the logic means, a muting signal which disallows the external output of the received optical signal for the predetermined period of time; and output stop means for stopping the external output of the received optical signal for the predetermined period of time, if the muting signal is input. - View Dependent Claims (2, 3)
- 1” and
-
4. A receiver which receives a transmitted optical signal as a digital signal constituted by a pulse train with a known pulse width,
the receiver comprising abnormal pulse detection means for detecting, by comparing the received optical signal with a reference digital signal generated based on the optical signal, a variation in pulse width in the optical signal being transmitted, and stopping external output of the received optical signal for a predetermined period of time if the variation in the pulse width is detected in the optical signal, wherein, the optical signal is input as a positive-logic digital signal constituted by a low level indicating a signal “ - 0” and
a high level indicating a signal “
1”
, andthe abnormal pulse detection means includes; incoming pulse edge detection means for detecting a moment of rise of the received optical signal and outputting a result of detection as an edge detection signal; reference pulse generation means for generating the reference digital signal as a negative-logic digital signal constituted by a low level indicating a signal “
1” and
a high level indicating a signal “
0”
, based on the edge detection signal output from the incoming pulse edge detection means;logic means for outputting a signal indicating a negative OR of the optical signal and the reference digital signal; muting signal generation means for generating, based on the signal indicating the negative OR output from the logic means, a muting signal which disallows the external output of the received optical signal for the predetermined period of time; and output stop means for stopping the external output of the received optical signal for the predetermined period of time, if the muting signal is input. - View Dependent Claims (5, 6)
- 0” and
Specification