Radar apparatus with determination of presence of target reflections
First Claim
1. A radar apparatus comprising:
- (a) means for transmitting an output signal such as one of optical, electromagnetic, and sonic wave signals;
(b) means for receiving a signal reflected by an external target;
(c) means for sampling the received signal at predetermined intervals;
(d) means for accumulating data according to the components of the sampled signal;
(e) means for storing the accumulated data;
(f) means for controlling said transmission, sampling, accumulation, and storage means; and
(g) means for reading the data out of the storage means and determining whether or not the data contain the reflected signal from the target.
1 Assignment
0 Petitions
Accused Products
Abstract
A low-cost compact radar apparatus measures a distance to a target and the relative speed of the target. The apparatus has a transmitter for transmitting a pulse signal and a receiver for receiving a reflected pulse signal from the target. The received signal is converted into a binary signal, which is sampled by a sampler and is accumulated in a cumulative storage unit. Addresses of the storage unit correspond to an interval between the transmission and reception of the pulse signal. According to the interval, the distance and relative speed of the target are calculated at high speed. The apparatus carries out many accumulation operations, to improve an S/N ratio and speedily detect even a weak reflected signal.
73 Citations
35 Claims
-
1. A radar apparatus comprising:
-
(a) means for transmitting an output signal such as one of optical, electromagnetic, and sonic wave signals; (b) means for receiving a signal reflected by an external target; (c) means for sampling the received signal at predetermined intervals; (d) means for accumulating data according to the components of the sampled signal; (e) means for storing the accumulated data; (f) means for controlling said transmission, sampling, accumulation, and storage means; and (g) means for reading the data out of the storage means and determining whether or not the data contain the reflected signal from the target. - View Dependent Claims (2, 3, 4, 13)
-
-
5. A radar apparatus comprising:
-
(a) means for transmitting an output signal such as one of optical, electromagnetic, and sonic wave signals; (b) means for receiving a signal reflected by an external target; (c) means for sampling the received signal at predetermined intervals; (d) means for accumulating data according to the components of the sampled signal; (e) means for storing the accumulated data; (f) means for controlling said transmission, sampling, accumulation, and storage means; (g) means for reading the data out of the storage means and determining whether or not the data contain the reflected signal from the target; (h) means for detecting an interference signal in the received signal; and (i) means for removing the detected interference signal. - View Dependent Claims (6, 7, 8, 9, 10, 11)
-
-
12. A radar apparatus comprising:
-
(a) means for transmitting an output signal such as one of optical, electromagnetic, and sonic wave signals; (b) means for receiving a signal reflected by an external target; (c) means for sampling the received signal at predetermined intervals; (d) means for accumulating data according to the components of the sampled signal; (e) means for storing the accumulated data; (f) means for controlling said transmission, sampling, accumulation, and storage means; (g) means for reading the data out of the storage means and determining whether or not the data contain the reflected signal from the target; (h) means for detecting an interval between sampling points where the received signal is detected; (i) means for preventing erroneous detection in detecting the interval between the sampling points; and (j) means for calculating the relative speed of the target according to the interval.
-
-
14. A radar apparatus comprising:
-
(a) means for transmitting an output signal such as one of optical, electromagnetic, and sonic wave signals; (b) means for receiving a reflected signal such as one of optical, electromagnetic, and sonic wave signals; (c) means for sampling the received signal at predetermined intervals, and thereafter, sampling noise; (d) means for accumulating data and noise according to the components of the sampled signal and noise; (e) means for storing the accumulated data and noise; (f) means for controlling said transmission, sampling, accumulation, and storage means; (g) means for detecting all levels of the sampled noise and employing the levels as thresholds for determining whether or not the accumulated data contain a reflected pulse from a target; and (h) means for reading the accumulated data and noise and determining whether or not the accumulated data contain the reflected pulse from the target according to the thresholds.
-
-
15. A radar apparatus comprising:
-
(a) a plurality of means for transmitting an output signal such as one of optical, electromagnetic, and sonic wave signals; (b) means for individually driving said transmission means at predetermined intervals; (c) means for receiving a reflected signal such as one of an optical, electromagnetic, and sonic wave signals; (d) means for sampling the received signal at predetermined intervals; (e) means for accumulating data according to the contents of the sampled signal; (f) means for storing the accumulated data; and (g) means for reading the accumulated data out of said storage means and determining whether or not the data contain a reflected pulse from an external target.
-
-
16. A radar apparatus comprising:
-
(a) means for periodically transmitting a pulse signal; (b) means for continuously receiving a signal in a direction in which the pulsesignal is reflected by a target; (c) means for converting the received signal into a binary signal; (d) means for sampling the binary signal at one or a plurality of different sampling points after said transmission means transmits the pulsesignal; (e) one or a plurality of means for accumulating values sampled at the sampling points, respectively, in response to each of a predetermined number of pulses in signals emitted from said transmission means; and (f) means for comparing a normalized value of the accumulated value of each of said accumulation means with a predetermined threshold and determining whether or not there is a reflected signal from the target according to a result of the comparison. - View Dependent Claims (17, 19, 20, 21, 22, 23, 24, 25)
-
-
18. A radar apparatus comprising:
-
(a) means for periodically transmitting a pulse signal; (b) means for continuously receiving a signal in a direction in which the pulsesignal is reflected by a target; (c) means for converting the received signal into a binary signal; (d) means for sampling the binary signal at a sampling point after said transmission means transmits the pulsesignal; (e) means for accumulating a value sampled at the sampling point in response to each of a predetermined number of pulsesignals emitted from said transmission means; (f) means for switching the sampling point to another once said accumulation means completes the accumulation of the predetermined number of sampled values at the sampling point, and letting said accumulation means accumulate sampled values at the new sampling point; (g) means for storing the accumulated values of the sampling points, respectively; (h) means for comparing a normalized value of each of the accumulated values stored in said storage means with a predetermined threshold and determining whether or not there is a reflected signal from the target according to a result of the comparison; and (i) means for calculating the distance to the target according to a time delay between the timing of said transmission means transmitting the pulsesignal and one of the sampling points that provides an accumulated value whose normalized value is greater than the threshold.
-
-
26. A radar apparatus comprising:
-
(a) transmission means for periodically transmitting a pulsesignal; (b) reception means for continuously receiving a signal in a direction in which the pulsesignal is reflected by a target; (c) means for converting the received signal into a binary signal; (d) means for sampling the binary signal in one or a plurality of different sampling periods after said transmission means transmits the pulsesignal; (e) one or a plurality of means for integrating the binary signal in the sampling periods, respectively, in response to each of a predetermined number of pulsesignals emitted from said transmission means; and (f) means for comparing a normalized value of the integrated value of each of said integration means with a predetermined threshold and determining whether or not there is a reflected signal from the target according to a result of the comparison. - View Dependent Claims (27, 29, 30, 31, 32, 33, 34, 35)
-
-
28. A radar apparatus comprising:
-
(a) means for periodically transmitting a pulse signal; (b) means for continuously receiving a signal in a direction in which the pulsesignal is reflected by a target; (c) means for converting the received signal into a binary signal; (d) means for sampling the binary signal in a sampling period after said transmission means transmits the pulsesignal; (e) means for integrating the binary signal sampled in the sampling period in response to each of a predetermined number of pulsesignals emitted from said transmission means; (f) means for switching the sampling period to another once said integration means completes a predetermined number of integral operations of the binary signal in the sampling period, and letting said integration means integrate the binary signal in the new sampling period; (g) means for storing the integrated values for the sampling periods, respectively; (h) means for comparing a normalized value of each of the integrated values stored in said storage means with a predetermined threshold and determining whether or not there is a reflected signal from the target according to a result of the comparison; and (i) means for calculating the distance to the target according to a time delay between the timing of said transmission means transmitting the pulsesignal and a sampling period that provides an integrated value whose normalized value is greater than the threshold.
-
Specification