JP2833872B2 - White noise generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a white noise generator for generating white noise of various power values, and more particularly to a white noise generator for generating a white noise signal corresponding to a signal power value specified from the outside. It is about.

[0002]

2. Description of the Related Art An example of a conventional white noise generator will be described with reference to FIG. As shown in FIG. 2, a conventional white noise generator includes a timing circuit 11 and a plurality of white noise signal generators 12-1, 12-2,.
-N. The generation of white noise is performed by a plurality of white noise signal generators 12-1, 12-2,..., 12-n that generate a white noise signal having a predetermined power value. The timing circuit 11 includes a white noise signal generator 12-
A timing signal k for extracting output sample values of 1, 12-2... 12-n is output. The white noise sample values are respectively output to output terminals 13-1, 13-2,... 1 in synchronization with a timing signal k which is an output of the timing signal 11.
3-n are output as white noise signals 1, m... N.

[0003]

In the conventional white noise generator, when generating a plurality of white noise signals having different power values, the white noise generators are required in the required number of power values of the white noise signal. There was a problem that there was. In addition, there is a problem in that fine adjustment of the power value of the white noise signal requires a complicated peripheral circuit.

[0004]

According to the present invention, there is provided a white noise generator for generating a white noise signal corresponding to a signal power value specified from the outside, for extracting a sample output from the white noise signal generator. A timing circuit for outputting a first timing signal and a second timing signal for extracting a multiplication coefficient corresponding to an output white noise signal power value;
A white noise signal generator for generating a white noise sample value of a reference power value in synchronization with the first timing signal output from the timing circuit; a plurality of externally designated power values and a power adjustment coefficient And a coefficient selection circuit that outputs a multiplication coefficient and a holding selection signal in synchronization with the second timing signal output from the timing circuit, a multiplication coefficient output from the coefficient selection circuit, and the white noise A multiplier for multiplying by a reference power value white noise sample value which is an output of the signal generator; and a white noise sample value calculated by the multiplier as an input. And a holding circuit for holding and outputting a white noise sample value for each noise power.

[0005]

According to the present invention, white noise is generated by a timing circuit, a white noise signal generator having a reference power value, and a multiplier.

[0006]

FIG. 1 is a block diagram showing an embodiment of a white noise generator according to the present invention. In FIG. 1, reference numeral 1 denotes a timing at which a timing signal a for extracting an output sample value of a white noise signal generator and a timing signal b for extracting a multiplication coefficient corresponding to an output white noise signal power value are output. The circuit 2 is a white noise signal generator that generates a white noise sample value of a reference power value in synchronization with a timing signal a output from the timing circuit 1, and 3 is a plurality of externally specified power values. A coefficient selection circuit which receives a power adjustment coefficient as an input and outputs a multiplication coefficient and a hold selection signal in synchronization with a timing signal b which is an output of the timing circuit 1, and a multiplication coefficient c which is an output of the coefficient selection circuit 3 A multiplier 5 multiplies a reference noise value d (reference white noise signal) which is an output of the white noise signal generator 2, and 5 is a white noise target calculated by the multiplier 4. A holding circuit for holding output white noise sample values for each desired noise power according to a is held selection signal f output of the coefficient selection circuit 3 inputs the value e. .. 7-n are input terminals for specifying power values, and 8-1, 8-2... 8-n are holding circuits. 5 is an output terminal from which white noise signals h, i.

Next, the operation of the embodiment shown in FIG. 1 will be described. First, the timing circuit 1 includes a timing signal a for extracting an output sample value of the white noise signal generator 2;
A timing signal b for extracting a multiplication coefficient according to the power of the white noise signal to be output is output. Then, the white noise signal generator 2 generates a white noise signal sample value d having a reference power value in synchronization with the timing signal a output from the timing circuit 1. Next, the coefficient selection circuit 3 calculates the power value specified from the input terminals 7-1, 7-2,... 7-n and the power adjustment coefficient g specified from the input terminal 6,
A multiplication coefficient and a holding selection signal corresponding to a desired power value are output in synchronization with a timing signal b output from the timing circuit 1. Then, the multiplier 4 multiplies the multiplication coefficient c output from the coefficient selection circuit 3 by the reference power value white noise signal d output from the white noise signal generator 2 to obtain the white noise of the specified power value. The signal is calculated. By performing the multiplication by the multiplier 4, fine adjustment of the power value can be easily performed. The white noise sample value e, which is the white noise signal calculated by the multiplier 4, is held by the holding circuit 5 for each desired noise power value in accordance with the holding selection signal f output from the coefficient selection circuit 3, and each output terminal 8 , 8-2... 8-n as white noise signals h, i.

[0008] The white noise generator of the present invention has a DS
Built-in ROM (Read Only Memory) as reference noise generator using P (Digital Signal Processor)
Can be easily realized by using a built-in multiplier as a multiplication operation unit.

[0009]

As described above, the white noise generator of the present invention generates white noise by the timing circuit, the white noise signal generator of the reference power value, and the multiplier. One white noise signal generator is provided. And a multiplier, and has an effect that the circuit scale can be significantly reduced as compared with the conventional case where a plurality of white noise generators are required. In addition, there is an effect that fine adjustment of the noise power value, in which the peripheral circuit is complicated in the conventional method, can be easily realized.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an embodiment of a white noise generator according to the present invention.

FIG. 2 is a block diagram showing an example of a conventional white noise generator not using the present invention.

[Description of Signs] 1 Timing circuit 2 White noise signal generator 3 Coefficient selection circuit 4 Multiplier 5 Holding circuit

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-60-49436 (JP, A) JP-A-54-6672 (JP, A) JP-A-51-111041 (JP, A) JP-A-51- 24843 (JP, A) JP-A-62-76905 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H03B 29/00 G01R 31/3183 G06F 7/58 H03K 3/84

Claims (1)

(57) [Claims] 1. A white noise generator for generating a white noise signal corresponding to a signal power value specified from the outside, a first timing signal for extracting an output sample value of the white noise signal generator, and an output. A second timing signal for extracting a multiplication coefficient corresponding to the white noise signal power value, and a reference power value synchronized with the first timing signal output from the timing circuit A white noise signal generator for generating a white noise sample value, a plurality of externally designated power values and a power adjustment coefficient, and the second circuit as an output of the timing circuit.
A coefficient selection circuit that outputs a multiplication coefficient and a hold selection signal in synchronization with the timing signal of the above, a multiplication coefficient that is an output of the coefficient selection circuit, a reference power value that is an output of the white noise signal generator, and a white noise sample value. And a holding unit that receives the white noise sample value calculated by the multiplier and holds and outputs the white noise sample value for each desired noise power in accordance with a holding selection signal output from the coefficient selection circuit. A white noise generator characterized by comprising a circuit.