Physical code channel activating detection method and apparatus based on channel estimating postprocessing

Abstract

The invention provides a physical code-channel activation and detection method based on channel estimation post-treatment and a device thereof. The method of the invention comprises the following steps: the power of all windows of the user is acquired; the window with the largest power amongst all windows and the position of the window with the largest power of the user are ascertained; activatedwindows amongst all windows of the user are ascertained according to the window with the largest power and the position of the window with the largest power; the actual total number of the activated physical code-channels of the user and the corresponding activated physical code-channels are ascertained according to the activated windows and the resource of the physical code-channels distributed to the user by the high level. The method and device of the invention effectively solve the problem of unreliability of estimation of key parameters, such as frequency deviation, etc. caused by lacking of data quantity, thus enhancing the performance of the system.

Description

technical field [0001] The present invention relates to the field of wireless communication systems, in particular to a physical code channel activation detection method and device based on channel estimation post-processing of a joint detection receiver applied in a TD-SCDMA (Time Division-Synchronous Code Division Multiple Access) system. [0002] Background technique [0003] The structure of the TD-SCDMA system receiver is as follows figure 1 As shown, the receiver processes the received signal using joint detection technology, and then outputs the demodulated data. Joint detection is mainly used to remove multiple access interference, multipath interference and intersymbol interference from the received signal. . As shown, the receiver includes: [0004] The data separator receives the JD (Joint Detection, joint detection) input signal e, the input signal is 864 chips, after the signal e passes through the data separator, it is divided into eMidamble training sequenc...

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Problems solved by technology

[0014] The working process of the above components constitutes the joint detection process of the receiver. In the actual system, in order to improve the reliability of the system, it is necessary to calculate some parameters, such as the carrier Frequency offset, signal-to-interference ratio and amplitude-to-noise ratio, etc. Some of these parameters depend on the demodulation output signal deq of joint detection and the number of code channels activated by the detected users in the post-processing of channel estimation , but since the joint detection receiver demodulates in units of subframes, and the TFCI (Transport Format Combination Indication, the receiver obtains the parameters of the sender's transmission format through the TFCI detection) received by the receiver is in units of radio frames Before encoding and decoding, the receiver cannot distinguish the number of physical code channels activated by the user in the current subframe before obtaining the TFCI decoding result. Therefore, when estimating parameters such as frequency offset, signal-to-interference ratio, and amplitude-to-noise ratio, in order to apply For all possible scenarios, usually only use the output data of the first active physical code channel (such as the smallest active physical code channel) in the current subframe for estimation, and compare the spreading factor of a single code channel When it is large, such as when the spreading factor is 16 (the range of the spreading factor of the TD-SCDMA system code channel is 1 to 16), the user's parameters used for estimating the above parameters such as offset frequency, signal-to-interference ratio and amplitude-to-noise ratio The amount of data to activate the physical code channel is relatively small, which will cause a large error in the estimation of these parameters, and does not take advantage of the stability of the system

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