Reception time determining apparatus and distance measuring apparatus using the same
First Claim
1. A reception time determining apparatus which measures the reception time of a transmission signal from a transmitter,wherein said transmission signal is a signal which produces a demodulation signal in which a signal change portion is unevenly distributed on a time axis and the waveform thereof is continuous on the time axis,said apparatus comprising:
- a demodulation section which demodulates a reception signal and outputs said demodulation signal;
a signal change portion detection section which detects said signal change portion contained in said demodulation signal which is output from said demodulation section, and outputs a signal change portion detection signal; and
a first time measurement section which measures a reception time of said reception signal based on said signal change portion detection signal output from said signal change portion detection section,wherein said signal change portion detection section comprises a band pass filter configured to pass at least one portion of frequency components contained in said signal change portion and to inhibit frequency components comprising a main lobe of the power spectrum of said demodulation signal, andwherein said first time measurement section measures said reception time based on an output signal of said band pass filter.
1 Assignment
0 Petitions
Accused Products
Abstract
The invention provides a reception time determining apparatus which can measure reception time to a high accuracy, without expanding an occupied bandwidth, and a distance measuring apparatus which uses the reception time determining apparatus.
There is provided a reception time determining apparatus (11, 111) where a transmitter (1, 100) sends a transmission signal which produces a demodulation signal in which a signal change portion is unevenly distributed on a time axis, and there is provided: a demodulation section (12, 112) which receives and demodulates this transmission signal and outputs a demodulation signal in which a signal change portion is unevenly distributed on a time axis; a signal change portion detection section (13, 113) which detects the signal change portion of the demodulation signal which is output from the demodulation section (12, 112), and outputs a signal change portion detection signal; and a time measurement section (14, 114) which measures a reception time of the reception signal based on the signal change portion detection signal output from the signal change portion detection section (13, 113).
-
Citations
10 Claims
-
1. A reception time determining apparatus which measures the reception time of a transmission signal from a transmitter,
wherein said transmission signal is a signal which produces a demodulation signal in which a signal change portion is unevenly distributed on a time axis and the waveform thereof is continuous on the time axis, said apparatus comprising: -
a demodulation section which demodulates a reception signal and outputs said demodulation signal; a signal change portion detection section which detects said signal change portion contained in said demodulation signal which is output from said demodulation section, and outputs a signal change portion detection signal; and a first time measurement section which measures a reception time of said reception signal based on said signal change portion detection signal output from said signal change portion detection section, wherein said signal change portion detection section comprises a band pass filter configured to pass at least one portion of frequency components contained in said signal change portion and to inhibit frequency components comprising a main lobe of the power spectrum of said demodulation signal, and wherein said first time measurement section measures said reception time based on an output signal of said band pass filter. - View Dependent Claims (2, 3, 4)
-
-
5. A reception time determining apparatus which measures the reception time of a transmission signal from a transmitter, wherein said transmission signal is a signal which produces a demodulation signal for which a singularity exists locally on a time axis, and in which the signal level of the demodulation signal is continuous, said apparatus comprising:
-
a demodulation section which demodulates a reception signal and outputs said demodulation signal; a singularity detection section which detects said singularity contained in said demodulation signal which is output from said demodulation section and outputs a singularity detection signal; and a first time measurement section which measures a reception time of said reception signal based on said singularity detection signal output from said singularity detection section, wherein said singularity is a discontinuity appearing in an M-th order differential of a waveform of said demodulation signal in which M is a natural number. - View Dependent Claims (6, 7, 8, 9, 10)
-
Specification