Method, system and device for transmitting demodulation reference signal and demodulating channel over backhaul link

Patent metadata

Field	Value
Publication number	US-9077495-B2
Application number	US-201013499250-A
Country	US
Kind code	B2
Filing date	Sep 28, 2010
Priority date	Sep 29, 2009
Publication date	Jul 7, 2015
Grant date	Jul 7, 2015

Abstract

The present invention discloses a method on a Long Term Evolution-Advanced (LTE-A) system backhaul link for demodulation pilot transmission, wherein the method includes that: among the resource areas occupied by a Relay-Physical Downlink Shared Channel (R-PDSCH) on the backhaul link, a base station selects the resource units which are preconfigured for sending the demodulation pilot signal of the R-PDSCH; the base station sends the demodulation pilot signal to a Relay Node (RN) belonging to the base station by using the selected resource units. The present invention also discloses a channel demodulation method on the LTE-A system backhaul link, an LTE-A communication system and device. The demodulation performance of the R-PDSCH in the LTE-A system can be ensured with the present invention.

First claim

What is claimed is:

1. A method for transmitting a demodulation reference signal over a backhaul link in a Long Term Evolution-Advanced, LTE-A, system, comprising:
selecting, by an eNodeB in a resource zone occupied by a Relay-Physical Downlink Shared Channel, R-PDSCH, over the backhaul link, preconfigured resource units for transmission of a demodulation reference signal of the R-PDSCH; and
transmitting, by the eNodeB, the demodulation reference signal to a Relay Node, RN, subordinated to the eNodeB in the selected resource units,
wherein configuring the resource units for transmission of the demodulation reference signal of the R-PDSCH comprises:
determining the resource zone occupied by the R-PDSCH;
selecting resource units in the resource zone, which are neither occupied by a common reference signal nor located at a last OFDM symbol of the resource zone; and
configuring the selected resource units as the resource units for transmission of the demodulation reference signal of the R-PDSCH;
wherein in a case that a Code Division Multiplexing-Time, CDM-T, mode is adopted for the demodulation reference signal and a number of OFDM symbols covered by a resource zone occupied by a Relay-Physical Downlink Control Channel, R-PDCCH, over the backhaul link is less than or equal to 2, and wherein the selecting the resource units in the resource zone, which are neither occupied by the common reference signal nor located at the last OFDM symbol of the resource zone comprises:
searching the resource zone occupied by the R-PDSCH for resource units in an LTE system for transmission of the demodulation reference signal;
translating the located resource units at last two OFDM symbols of the resource zone occupied by the R-PDSCH onto resource units in the resource zone occupied by the R-PDSCH, which are not occupied by the common reference signal; and
selecting the located resource units at first two OFDM symbols of the resource zone occupied by the R-PDSCH and the translated resource units as the resource units in the resource zone, which are neither occupied by the common reference signal nor located at the last OFDM symbol of the resource zone;

or
wherein in a case that a Code Division Multiplexing-Time, CDM-T, mode is adopted for the demodulation reference signal and a number of OFDM symbols covered by a resource zone occupied by a Relay-Physical Downlink Control Channel, R-PDCCH, over the backhaul link is larger than 2, and wherein the selecting the resource units in the resource zone, which are neither occupied by the common reference signal nor located at the last OFDM symbol of the resource zone comprises:
searching the resource zone occupied by the R-PDSCH for resource units in an LTE system for transmission of the demodulation reference signal;
translating the located resource units at last two OFDM symbols of the resource zone occupied by the R-PDSCH onto resource units in the resource zone occupied by the R-PDSCH, which are not occupied by the common reference signal; and
selecting the translated resource units as the resource units in the resource zone, which are neither occupied by the common reference signal nor located at the last OFDM symbol of the resource zone.

2. The method according to claim 1 , wherein in a case that a Code Division Multiplexing-Frequency, CDM-F, mode is adopted for the demodulation reference signal, and selecting the resource units in the resource zone, which are neither occupied by the common reference signal nor located at the last OFDM symbol of the resource zone comprises:
searching the resource zone for resource units in an Long Term Evolution, LTE, system for transmission of the demodulation reference signal; and
selecting the located resource units as the resource units in the resource zone, which are neither occupied by the common reference signal nor located at the last OFDM symbol of the resource zone.

3. The method according to claim 2 , wherein the resource units for transmission of the demodulation reference signal of the R-PDSCH comprises:
resource units consisted of third OFDM symbols in a second timeslot of a sub-frame where the resource zone is located.

4. The method according to claim 1 , wherein in a case that the CDM-T mode is adopted for the demodulation reference signal and the number of OFDM symbols covered by a resource zone occupied by a R-PDCCH over the backhaul link is less than or equal to 2 and wherein the resource units for transmission of the demodulation reference signal of the R-PDSCH comprises:
resource units consisted of the sixth OFDM symbols and the seventh OFDM symbols in a first timeslot of a sub-frame where the resource zone occupied by the R-PDSCH is located, and resource units consisted of third OFDM symbols and fourth OFDM symbols in a second timeslot of the sub-frame.

5. The method according to claim 1 , wherein in a case that the CDM-T mode is adopted for the demodulation reference signal and the number of OFDM symbols covered by a resource zone occupied by a R-PDCCH over the backhaul link is larger than 2 and wherein the resource units for transmission of the demodulation reference signal of the R-PDSCH comprises:
resource units consisted of third OFDM symbols and fourth OFDM symbols in a second timeslot of a sub-frame where the resource zone occupied by the R-PDSCH is located.

6. The method according to claim 1 , wherein transmitting by the eNodeB the demodulation reference signal to the RN subordinated to the eNodeB in the selected resource units comprises:
transmitting, by the eNodeB, the demodulation reference signal to the RN in a part of the selected resource units at a preset value of a density of reference signals.

7. A method for demodulating a channel over a backhaul link in a Long Term Evolution-Advanced, LTE-A, system, comprising:
determining, by a Relay Node, RN, locations of resource units in which an eNodeB transmits a demodulation reference signal of a Relay-Physical Downlink Shared Channel, R-PDSCH, and which are located in a resource zone occupied by the R-PDSCH, and receiving the demodulation reference signal at the locations; and
performing, by the RN, channel estimation with the demodulation reference signal and demodulating the R-PDSCH with a result of channel estimation,
wherein the resource units in which the eNodeB transmits the demodulation reference signal of the R-PDSCH comprise:
resource units in the resource zone, which are neither occupied by a common reference signal nor located at a last OFDM symbol of the resource zone;
wherein in a case that a Code Division Multiplexing-Time, CDM-T, mode is adopted for the demodulation reference signal and the number of OFDM symbols covered by a resource zone occupied by a Relay-Physical Downlink Control Channel, R-PDCCH, over the backhaul link is less than or equal to 2, determining by the RN the locations of the resource units in which the eNodeB transmits the demodulation reference signal of the R-PDSCH comprises:
locating, in the resource zone occupied by the R-PDSCH, resource units in an LTE system for transmission of the demodulation reference signal;
translating the located resource units at last two OFDM symbols of the resource zone occupied by the R-PDSCH onto resource units in the resource zone occupied by the R-PDSCH, which are not occupied by a common reference signal; and
determining locations of the located resource units at first two OFDM symbols of the resource zone occupied by the R-PDSCH and the translated resource units as the locations of the resource units in which the eNodeB transmits the demodulation reference signal;

or
wherein in a case that a Code Division Multiplexing-Time, CDM-T, mode is adopted for the demodulation reference signal and the number of OFDM symbols covered by a reso

Assignees

• Wang Libo
• Pan Xueming
• Xiao Guojun
• Miao Deshan
• Zhang Wenjian
• China Academy Of Telecomm Tech

Inventors

• Wang Libo
• Pan Xueming
• Xiao Guojun
• Miao Deshan
• Zhang Wenjian

Classifications

• H04W84/047

  using dedicated repeater stations · CPC title

• H04B7/15542

  Selecting at relay station its transmit and receive resources (selection of wireless resources by user or terminal H04W72/02; arrangements affording multiple use of the transmission path by two-dimensional division of the resources H04L5/0003, or by allocating sub-channels H04L5/003) · CPC title

• H04W48/08

  Access restriction or access information delivery, e.g. discovery data delivery (signalling during connection H04W76/00) · CPC title

• H04W72/0453

  Resources in frequency domain, e.g. a carrier in FDMA · CPC title

• H04L5/0048 Primary

  Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091) · CPC title