Method for extracting iterference signal information and apparatus for the same

Abstract

A method and apparatus are provided for extracting interference signal information. The method includes demodulating control channel signals received from serving and adjacent cells; decoding the control channel signals received from the serving cell to extract control information; decoding the control channel signals received from the adjacent cell; extracting, at each subframe, from the decoded control channel signals received from the adjacent cell, a terminal ID of the adjacent cell; accumulating the extracted terminal IDs; filtering only a control channel signal from among the control channel signals received from the adjacent cell corresponding to a terminal ID having an accumulation count that is greater than or equal to a threshold; determining a reliability value of the filtered control channel signal; identifying the filtered control channel signal as a first interference signal, based on the reliability value; and extracting interference signal information based on the first interference signal.

Description

PRIORITY[0001]This application claims priority under 35 U.S.C. §119(a) to U.S. Provisional Patent Application Ser. No. 61 / 948,873, which was filed on Mar. 6, 2014, and Korean Patent Application No. 10-2014-0132612, which was filed on Oct. 1, 2014, the content of each of which is hereby incorporated.BACKGROUND[0002]1. Field of the Disclosure[0003]The present disclosure relates generally to a method and apparatus for extracting interference signal information without additional signaling from a network in a communication system.[0004]2. Description of Related Art[0005]Generally, in a cellular-based communication system, a terminal (e.g., a User Equipment (UE), a Mobile Station (MS), etc.) may suffer from interference caused by a signal from another terminal that uses the same resources in the same cell, and / or from another terminal in an adjacent cell. In this case, the terminal may detect or remove the interference signal from the signal that the terminal should receive, using an int...

AI Technical Summary

Benefits of technology

This approach increases the accuracy of interference signal extraction and improves interference cancellation and data reception performance by reducing false alarms and enhancing the terminal's ability to identify and filter out interference signals effectively.

Problems solved by technology

Generally, in a cellular-based communication system, a terminal (e.g., a User Equipment (UE), a Mobile Station (MS), etc.) may suffer from interference caused by a signal from another terminal that uses the same resources in the same cell, and / or from another terminal in an adjacent cell.

However, if the terminal demodulates and decodes only the target signal without information about the interference signal, performance degradation caused by the interference signal may increase, and this phenomenon may be more severe at the terminal in the boundary of the cell.

Using blind detection, the terminal may reduce false alarms or misdetection probability with filtering techniques, but it is difficult to make correct filtering determinations, thereby limiting performance improvement of the interference cancellation function.

However, each terminal may not know a UE-ID of another terminal since the terminal receives only its own UE-ID through upper-level signaling.

However, if there is a terminal that uses the same frequency-time resources in the same cell as that of the terminal, or if a base station of another cell is transmitting data to another terminal using the same frequency-time resources, the terminal may experience performance degradation due to the interference problems, when receiving data.

Although various methods have been proposed to solve the interference problems in a terminal, the actual performance improvement is limited if the terminal does not have information as to whether a signal is an interference signal.

However, because a terminal generally does not know information about UE-IDs of other terminals, the terminal may not extract a DCI of another terminal, in which information about the interference signal is present, so the terminal may not use an improved algorithm such as joint detection.

However, if the base station does provide this information about the UE-ID in the interference signal, this will increase the overhead of the control channel.

However, if the blind decoding scheme used for decoding a control channel of another terminal is applied, the terminal should perform decoding for all the detection locations of the full band and the DCI formats because the terminal does not know the RNTI of the other terminals, increasing the likelihood of RNTI false alarms.

However, in the soft metric-based filtering scheme, even though a soft metric value is large, a false alarm other than a desired UE-ID value may be generated.

In particular, if an AL is low, a false alarm is likely to occur.

However, in the UE-ID based filtering scheme, multiple RNTI candidates still exist, even after undergoing filtering, so a possibility of the false alarm is high.

That is, even though both of the current two techniques are used, the false alarm possibility of falsely estimating a UE-ID is high.

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