JPH0388535A - Received data processor - Google Patents

Abstract

PURPOSE:To reduce errors of data due to an impulse noise by determining respective bits of received data according to plural sampling data. CONSTITUTION:A sampling part 8 samples the received data S1 with a clock CK2 and supplies the sampled data to a data determination part 7. The data determination part 7 determines data by majority decision making with three sampled data S4 before and after the change point of a timing pulse S2 according to a change point detection signal S3. Consequently, the determined data S5 is supplied to a data storage part 3 and stored. Consequently, even if the impulse noise is generated in the received data S1, the correct data can be stored in the data storage part 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a received data processing device suitable for, for example, reducing the influence of impulse noise occurring in received data.

[Prior art] FIG. 3 shows N RZ (N on-Return to
This figure shows an example of the configuration of a circuit that receives a Z ero signal.

In the figure, received data S1 of an NRZ signal from a receiving section 1 is supplied to a data storage section (memory) 3 of a CPU 2.

Further, received data S1 from the receiving section 1 is supplied to a timing extraction circuit 4. This timing extraction circuit 4 generates a timing pulse S2 in synchronization with the received data S1, and this timing pulse S2 is supplied to the data storage section 3.

Then, in the data storage section 3, the received data S1 is sampled with the timing pulse S2, and the sampled data is stored in the data storage section 3.

For example, when the received data S1 is as shown in FIG. 4A, the timing pulse S2 is as shown in FIG. be done.

[Problem to be solved by the invention] By the way, according to the configuration shown in FIG.
As shown in Figure B, when impulse noise N occurs in the part corresponding to the →non-bringing point of the received data S1, erroneous data as shown in Figure E is stored in the data storage section 3 of the CPU 2. It will be stored.

Therefore, it is an object of the present invention to reduce data errors caused by impulse noise occurring in received data.

[! ! Means for Solving the Problem] The present invention provides timing extraction means for generating a timing pulse synchronized with received data, edge detection means for detecting a change point of the timing pulse from the timing extraction means, and a method for detecting received data. 1/n(n
is an integer of 2 or more); and data determining means determines the received data based on n pieces of sampling data from the sampling means before and after the change point detected by the edge detecting means. This is what happens.

[Function] In the above configuration, each bit of the received data is determined based on 11 pieces of sampling data, for example, by majority vote, so that data due to level fluctuations in a short time compared to the bit rate, such as impulse noise, is eliminated. errors can be reduced.

[Embodiment] An embodiment of the present invention will be described below with reference to FIG. This example is an example applied to a circuit that receives an NRZ signal. In FIG. 1, parts corresponding to those in FIG. 3 are designated by the same reference numerals, and detailed explanation thereof will be omitted.

In this example, the timing pulse S2 from the timing extraction circuit 4 is supplied to the edge detection section 5 and sampling timer 6 of the CPU 2.

Based on the timing pulse S2, the sampling timer 6 generates a clock CKI having a period of 1/10 of the bit period of the received data S1, and this clock CKI is supplied to the edge detection section 5 as a sampling clock.

In the edge detection section 5, the timing pulse S2 is sampled using the clock CKI, and the changing point of the timing pulse S2, in this example, the falling edge is detected based on the sampling data. This change point detection signal S3 is then supplied to the data determining section 7.

Further, the received data S1 from the receiving section 1 is supplied to the sampling section 8 of the CPU 2. From the above-mentioned sampling timer 6, in addition to the clock CK 1, based on the timing pulse S2, 17 of the bit period of the received data S1 is sent.
A clock CK2 with a period of 3 is generated, and this clock C
K2 is supplied to the sampling section 8 as a sampling clock.

In the sampling section 8, the received data S1 is clocked at CK2.
The sampled data S4 is supplied to the data determining section 7.

In the data determining section 7, data is determined by majority vote from three pieces of sampling data S4 before and after the changing point of the timing pulse S2, based on the changing point detection signal S3.

The determined data S5 is then supplied to the data storage section 3 and stored therein.

In the above configuration, for example, the received data S1 is
As shown in Figure A, the timing pulse S2 is
The clock CK2 becomes as shown in FIG. Therefore, the sampling data S4 from the sampling unit 8 becomes as shown in FIG.
The data determining section 7 outputs determined data S5 as shown in FIG.

Furthermore, as shown in Figure B, if impulse noise N occurs in the portion corresponding to the sampling point of the received data S1, the sampling data S4 from the sampling section 8 becomes as shown in Figure G. , the data determining section 7 outputs determined data S5 as shown in H in the figure, and is stored in the data storage section 3 of the CPU 2. That is, in this case as well, the data storage section 3 stores the same data as in the case where the impulse noise N does not occur.

As described above, according to this example, even if impulse noise occurs in the received data S1, correct data can be stored in the data storage section 3.

In the above-mentioned embodiment, the received data is sampled with the clock CK2 having a period of 1/3 of the bit period of the received data S1, and the data is determined based on three pieces of sampling data. However, the invention is not limited thereto. In other words, 1/n of the bit period of the received data S1 (n is an integer greater than or equal to 2)
By sampling the received data with the clock CK2 having a period of , and determining the data based on n pieces of sampling data, it is possible to obtain the same effects as in the above-described embodiment. In this case, if the data determining unit 7 determines the data by majority vote, it is preferable that n be an odd number as in the above embodiment.

[Effects of the Invention] As explained above, according to the present invention, each bit of received data is determined based on a plurality of pieces of sampling data, so data errors caused by impulse noise can be reduced. . Therefore, if this invention is applied particularly to low-speed wireless data transmission, even if instantaneous level fluctuations occur due to fading etc. during mobile communication, if the level fluctuations are short compared to the bit rate, the data will be correctly transmitted. There are benefits that can be received.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is an explanatory diagram of its operation, Fig. 3 is a block diagram of a conventional example, and Fig. 4 is a block diagram of a conventional example.
FIG. 6 is an explanatory diagram of the operation of the illustrated example. Receiving section PU Data storage section Timing extraction circuit, edge detection section, sampling timer, data confirmation section, sampling section

Claims (1)

[Claims] (1) A timing extraction means for generating a timing pulse synchronized with the received data; an edge detection means for detecting a change point of the timing pulse from the timing extraction means; sampling means for sampling at a period of (n is an integer of 2 or more); and data determination for determining received data based on the n pieces of sampling data from the sampling means before and after the change point detected by the edge detection means. A received data processing device comprising means.