Iterative method of decoding a received signal

#The present invention relates to an iterative method of decoding a received signal transmitted in data frames.

#The invention relates, in addition, to an iterative method of decoding received signals transmitted in data frames via various channels.

#Furthermore, the present invention relates to a device for decoding received signals by means of an iterative method.

#Further features, possible applications and advantages of the invention emerge from the description below of the exemplary embodiments of the invention that are shown in the drawing. In this connection, all the features described or presented separately or in any combination form the subject of the invention, regardless of their inclusion in the patent claims or of their back-reference and also regardless of their formulation or presentation in the description or in the drawing.

#In the drawing:

#FIG. 1 shows a block diagram of a decoding device according to the invention;

#FIG. 1 shows a block diagram of a decoding device according to the invention in accordance with a preferred embodiment. The decoding device is denoted in its entirety by the reference symbol 20. An input signal transmitted in data frames and applied to the decoding device 20 is denoted by the reference symbol 21. The input signal 21 is, for example, an uplink signal of a mobile radio unit of a radio telecommunications system that is received in a base station of the radio telecommunications system. The input signal 21 is applied to an unpuncturing and demultiplexing unit 22, which generates an output signal e and two redundancy signals y1, y2 for the purpose of error correction. The output signal e and the first redundancy signal y1 are applied to a first constituent decoder 23, which is constructed, for example, as a Viterbi decoder. It may, however, also be constructed as a so-called MAP, Log-MAP or MaxLogMAP decoder. An output 24 of the first decoder 23 is fed to an interleave unit 25. An output of the interleave unit 25 and the second redundancy signal y2 are fed to the input of a second constituent decoder 26, which may be constructed, for example, as a Viterbi decoder. A decoded signal 33 is fed back again via a feedback 27 and a de-interleave unit 28 disposed therein to the input of the first decoder 23. To this extent, the decoding device 20 according to the invention is similar to a decoding device known from the prior art shown in FIG. 2.

#In contrast to the known decoding device, the decoding device 20 according to the invention has, however, a device 32 for performing a cyclic redundancy check (CRC) following every iteration run. The quality of the decoded signal 33 can be checked with the aid of the CRC. If the CRC reveals that the data frame under consideration of the decoded signal 33 is not error-free and that the decoded signal 33 does not therefore have the specified quality (as yet), the decoded signal 33 is fed back via the feedback 27 to the input of the first decoder 23 and is decoded once again within the framework of a further iteration.

#If the data frame of the decoded signal 33 is, however, error-free, the decoded signal 33 is emitted as estimated hard bits 31 via a threshold detector 29 for converting the soft output of the decoder 26 into a hard output and a further de-interleave unit 30.