Patent ID: 7826344
Filing Date: 2010-11-02
Classification: H04B,H04L

Abstract:
1. A method for transmitting reference signals in a Broadband Wireless Access (BWA) communication system including a first transmit antenna, a second transmit antenna, and a plurality of sub-carriers, each of the sub-carriers occupying a sub-frequency domain, the method comprising the steps of: (1) transmitting reference signals for identifying the first transmit antenna through a second predetermined number of sub-carriers in a first mini sub-channel, the first mini sub-channel being transmitted through the first transmit antenna and occupied by a predetermined time domain and sub-frequency domains of a first predetermined number of sub-carriers, wherein, after the second predetermined number of sub-carriers in the first mini sub-channel are truncated by using a truncation scheme, the reference signals are inserted in the truncated second predetermined number of sub-carriers in the first mini-sub-channel and transmitted; and (2) transmitting reference signals for identifying the second transmit antenna through the second predetermined number of the sub-carriers in a second mini sub-channel, the second mini sub-channel being transmitted through the second transmit antenna and occupied by the time domain and the sub-frequency domains of the first predetermined number of sub-carriers wherein, after the second predetermined number of sub-carriers in the second mini-sub-channel are truncated by using the truncation scheme, the reference signals are inserted in the truncated second predetermined number of sub-carriers in the second mini sub-channel and transmitted, wherein the sub-carriers through which the reference signals for identifying the first transmit antenna are transmitted comprise sub-frequency domains different from the sub-frequency domains occupied by the sub-carriers through which the reference signals for identifying the second transmit antenna are transmitted, wherein transmitting the reference signals for identifying the first transmit antenna further comprises transmitting null data in the first mini sub-channel through sub-carriers including sub-frequency domains that are identical to the sub-frequency domains of the sub-carriers for transmitting the reference signal for identifying the second transmit antenna, wherein transmitting the reference signals for identifying the second transmit antenna further comprises transmitting null data in the second mini sub-channel through sub-carriers including sub-frequency domains that are identical to the sub-frequency domains of the sub-carriers for transmitting the reference signals for identifying the first transmit antenna, wherein the reference signals for identifying the first and second transmit antennas are inserted into sub-carriers that were previously allocated to data tones before the truncation by using the truncation scheme, and wherein coded symbols to be transmitted include systematic symbols and parity symbols, and only the parity symbols arc truncated according to the truncation scheme.