Pilot signal transmitting method, and channel estimation method, apparatus, and system

摘要

Embodiments of the present invention disclose a pilot signal transmitting method, and a channel estimation method, an apparatus, and a system. The method includes: within a transmission time interval (TTI), transmitting a first pilot signal (CPICH1) on a first antenna, and transmitting a second pilot signal (CPICH2) on a second antenna; when no first-type terminal is scheduled within coverage of a MIMO system within the TTI, transmitting a third pilot signal (CPICH3) on a third antenna, and transmitting a fourth pilot signal (CPICH4) on a fourth antenna; and when a first-type terminal is scheduled within the coverage of the MIMO system within the TTI, transmitting the CPICH3 and a fifth pilot signal (CPICH5) on the third antenna, and transmitting the CPICH4 and a sixth pilot signal (CPICH6) on the fourth antenna. By using the method, interference of a pilot signal to a legacy terminal can be greatly reduced.

主权项

1. A pilot signal transmitting method for transmitting a pilot signal in a multiple-input multiple-output (MIMO) system, the method comprises:
within a transmission time interval (TTI), transmitting a first pilot signal (CPICH1) on a first antenna, and transmitting at least a portion of a second pilot signal (CPICH2) on a second antenna; and when no first-type terminal is scheduled within coverage of the MIMO system within the TTI, transmitting a third pilot signal (CPICH3) on a third antenna, and transmitting a fourth pilot signal (CPICH4) on a fourth antenna; when no legacy terminal is scheduled within coverage of the MIMO system within the TTI, decomposing the CPICH2 into a CPICH2s and a CPICH2e and, when no first-type terminal is scheduled within coverage of the MIMO system within the TTI, transmitting the CPICH2s but not the CPICH2e on the second antenna; wherein the CPICH1 is used for channel state information (CSI) estimation and data demodulation, the CPICH2 is used for CSI estimation and data demodulation, CPICH2s is a pilot signal required for performing CSI estimation, the CPICH2e is a pilot signal required for performing data demodulation, the CPICH3 is a pilot signal required for performing CSI estimation, and the CPICH4 is a pilot signal required for performing CSI estimation, the MIMO system comprises a 4 Branch MIMO system or an 8 Branch MIMO system, the first-type terminal is a 4 Branch MIMO terminal corresponding to the 4 Branch MIMO system, or a 4 Branch MIMO terminal or an 8 Branch MIMO terminal corresponding to the 8 Branch MIMO system, and wherein the legacy terminal is one of a single-input single-output terminal, a single-input 2-output terminal, or a 2 Branch MIMO terminal.