JP2985284B2 - Data decoding device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a data decoding device used for digital mobile communication and the like.

2. Description of the Related Art FIG. 2 shows a configuration of a conventional data decoding device.
In FIG. 2, reference numeral 1 denotes a phase quantizer for detecting the phase of a received signal. 2 indicates that the detected phase is 0, π / 2, π, −π /
This is a quadrant change detector that detects a time when any one of the phases 2 is reached, and is connected to the phase quantizer 1. Reference numeral 3 denotes a clock regenerator for averaging the time intervals detected by the quadrant change detector 2 to determine the intermediate time of the transmission data and outputting the time of the data change point from the intermediate time. It is connected. Reference numeral 4 denotes a data discriminator for discriminating the quantized phase at the data change point and decoding the data, and is connected to the phase quantizer 1 and the clock regenerator 3. Reference numeral 5 denotes a phase adjuster for detecting an error between the phase of the received signal and the originally transmitted phase, obtaining an adjustment amount, and correcting the reference phase of the phase quantizer. It is connected to the.

 Next, the operation of the above conventional example will be described.

In FIG. 2, a received signal is input to a phase quantizer 1 and its phase is detected. FIG. 3 shows an example of the detected phase. The horizontal axis indicates time t, and the vertical axis indicates phase θ, and transmission data is shown corresponding to time t. Next, the detected phase is input to the quadrant change detector 2, which detects a time at which this phase becomes any of 0, π / 2, π, and -π / 2. The detected time is sent to the clock regenerator 3,
The intermediate time of the transmission data is obtained by averaging the time intervals detected here, and the time of the change point of the transmission data from this is obtained and output to the data discriminator 4. The data discriminator 4 discriminates the quantized phase at the change point of the data and decodes the transmission data. Further, an error between the phase of the received signal and the phase to be transmitted is detected, and the phase adjuster 5 obtains an adjustment amount from the detected error and corrects the reference phase of the phase quantizer 1.

As described above, even with the conventional data decoding device, it is possible to decode the transmission data when the phase of the reception signal changes the quadrant at an intermediate time of the transmission data regardless of the data.

However, in the above-described conventional data decoding device, the time at which the quadrant of the phase of the received signal changes may not always be the intermediate time of the transmission data depending on the data to be transmitted. However, even if averaging is performed by a clock regenerator, there is a problem in that the discrimination time varies greatly, and thus correct transmission data cannot be decoded.

The present invention is to solve such a conventional problem, and to provide an excellent data decoding device that detects a correct identification time by reducing the variation of the identification time and thus can decode a correct transmission data. It is intended for.

Means for Solving the Problems In order to achieve the above object, the present invention provides a phase quantizer for detecting the phase of a received signal, and the phase quantizer is connected to the phase quantizer to differentiate the detected phase. A phase differentiator that detects a time change, and is connected to this phase differentiator, and outputs a discrimination clock by using the fact that the time when the output changes from positive to negative or from negative to positive coincides with the change time of the transmission data. And a data discriminator connected to the clock regenerator and the phase quantizer for decoding transmission data based on a phase value quantized at the time of the identification clock output from the clock regenerator. The optimum identification time is detected based on the change point of the increase and decrease of the quantized phase, and data is identified from the received signal.

Operation Therefore, according to the present invention, it is possible to extract the optimum identification clock based on the change point of the increase or decrease of the quantized phase, and obtain the correct identification time with a small variation to decode the correct data. This has the effect of

Embodiment FIG. 1 is a block diagram showing an embodiment of a data decoding device according to the present invention. The same parts as in the conventional example of FIG. 2 are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. In FIG. 1, 1 is a phase quantizer, 6 is connected to the phase quantizer 1, and a phase differentiator for obtaining a time change of the phase detected by the phase quantizer 1 is shown. A clock regenerator connected to output a discrimination clock by utilizing the time when the output of the phase differentiator 6 changes from positive to negative or from negative to positive matches the data change point. The data discriminator is connected to the clock regenerator 7 and decodes data based on the phase value quantized at the time of the identification clock output from the clock regenerator 7.

 Next, the operation of the above embodiment will be described.

In the above embodiment, the phase quantizer 1 receives a received signal and detects its phase. The detected phase is illustrated in FIG. The detected phase is sent to the phase differentiator 6 and the data discriminator 4. The phase differentiator 6 differentiates the input phase and detects a time change of the phase. In FIG. 3, for example, the time change of the phase changes from negative to positive at time 2T. The time change of the phase is sent to the clock regenerator 7, where the discrimination clock is generated by utilizing the fact that the time at which the time change of the phase changes from positive to negative or from negative to positive coincides with the data change point. , To the data identifier 4. The data discriminator 4 decodes the data based on the quantized phase value at the discrimination time output from the clock regenerator 7.

As described above, according to the above-described embodiment, correct identification is performed by utilizing that the time at which the increase / decrease value of the phase obtained by the phase differentiator 6 changes from positive to negative or from negative to positive always coincides with the data change point. There is an advantage that the time can be obtained with a small variation and data can be correctly decoded.

As is clear from the above embodiment, the present invention extracts the optimum identification clock based on the change point of the increase or decrease of the quantized phase, and corrects the correct identification time with a small variation. Thus, there is an advantage that correct data can be decoded by using the above method.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a data decoding device according to one embodiment of the present invention, FIG. 2 is a block diagram of a conventional data decoding device, and FIG. 3 is a timing chart showing a time change of phases of transmission data and a transmission signal. It is. 1 ... Phase quantizer, 4 ... Data discriminator, 6 ... Phase differentiator, 7 ... Clock regenerator.

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kazunori Inoki 4-3-1 Tsunashima Higashi, Kohoku-ku, Yokohama-shi, Kanagawa Prefecture Inside Matsushita Communication Industrial Co., Ltd. (72) Inventor Koichi Honma 4 Tsunashima-Higashi, Kohoku-ku, Yokohama, Kanagawa Prefecture Chome 3-1, Matsushita Communication Industrial Co., Ltd. (56) References JP-A-4-115739 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H04L 27/00-27 / 38

Claims (1)

(57) [Claims] A phase quantizer for detecting a phase of a received signal; a phase differentiator connected to the phase quantizer for differentiating the detected phase to detect a time change thereof; A clock regenerator connected to a clock generator for outputting an identification clock by utilizing that the time when the output changes from positive to negative or from negative to positive matches the change time of the transmission data; and the clock regenerator and the phase A data discriminator connected to the quantizer and decoding transmission data based on the quantized phase value from the quantizer at the time of the discrimination clock output from the clock regenerator. The optimal identification time is detected based on the change point of
A data decoding device for identifying data from a received signal.