Method for transmitting reference signals

Abstract

A method and apparatus for transmitting reference signals in a wireless communication system is disclosed. The method and apparatus includes reference signal, RS, transmission in resource blocks supporting multiple antenna port transmission, at least one broadcast channel being provided in resource blocks belonging to a first set of resource blocks, a first number of reference signals being transmitted in at least one resource block supporting multiple antenna port transmission and a second number of reference signals being transmitted in at least one resource block belonging to a second set of resource blocks. Preferably, different resource elements, REs, are used for each reference signal in resource blocks. An example embodiment of reference signal support of, e.g., eight antenna ports is provided.

1 . Method of reference signal transmission in resource blocks, RBs, supporting multiple antenna port transmission in a wireless communication system comprising:
 determining first and second mutually exclusive sets of RBs, at least one broadcast channel, BCH, being provided in RBs belonging to said first set of RBs;   transmitting a first number of reference signals, RSes, in at least one resource block, RB, supporting multiple antenna port transmission; and   transmitting a second number of RSes in at least one RB belonging to said second set of RBs.   
     
     
         2 . The method according to  claim 1 , wherein at least one synchronisation signal, SS, is provided in RBs belonging to said first set of RBs, and said at least one SS is a primary synchronisation signal, P-SS, or a secondary synchronisation signal, S-SS. 
     
     
         3 . The method according to  claim 1 , wherein said wireless communication system is a cellular wireless communication system further comprising,
 a first set of receive nodes, RNs, and a second set of receive nodes, RNs, and said first number of RSes are common to all RNs in a cell, and   said second number of RSs are common to all RNs belonging to said second set of RNs, and wherein   said first and second number of RSs are specific for said cell, and used for measurement, or used for measurement and demodulation.   
     
     
         4 . The method according to  claim 1 , wherein said RBs supporting multiple antenna port transmission are transmitted in SFs supporting multiple antenna port transmission, and wherein said SFs supporting multiple antenna port transmission are divided into a first and a second exclusive sets of SFs and said first set of RBs belongs to said first set of SFs, and wherein
 said first number of RSs are transmitted in at least one SF supporting multiple antenna port transmission, and   said second number of RSs are transmitted in at least one SF belonging to said second set of SFs.   
     
     
         5 . The method according to  claim 4 , wherein said second number of RSes are transmitted in every Nth SF, where N is an integer and N>1. 
     
     
         6 . The method according to  claim 4 , wherein said second number of RSes are transmitted in the second slot of said at least one SF belonging to said second set of SFs. 
     
     
         7 . The method according to  claim 6 , wherein said second number of RSes are transmitted in every one, or every Mth RB in said second slot, where M is an integer and M>1. 
     
     
         8 . The method according to  claim 1 , wherein an RB belonging to said second set of RBs comprises one of
 a physical downlink shared channel, PDSCH, region; and   a physical downlink shared channel, PDSCH region and
 a control region for at least a physical downlink control channel, PDCCH, 
 a physical control format indicator channel, PCFICH, or 
 a physical hybrid ARQ indicator channel, PHICH; 
   
       wherein said second number of reference signals RSes are transmitted in the PDSCH region in at least one RBs belonging to said second set of RBs. 
     
     
         9 . The method according to  claim 1 , wherein said at least one BCH is a physical broadcast channel, PBCH. 
     
     
         10 . The method according to  claim 1 , wherein said respective first and second numbers of RSes equals 4. 
     
     
         11 . The method according to  claim 1 , wherein said wireless communication system is an LTE-A system and said RSes are orthogonal to each other and provided in downlink, DL, transmission. 
     
     
         12 . The method in a receive node for receiving reference signals in a wireless communication system, in which a reference signal, RS, defines an antenna port, AP, for a transmit node, TN, and said TN is arranged to transmit a multiple of RSes in resource blocks, RBs, supporting multiple antenna port transmission, wherein said RBs supporting multiple antenna port transmission are divided into a first and a second exclusive sets of RBs, and at least one broadcast channel, BCH, is provided in RBs belonging to said first set of RBs, said method comprising:
 receiving a first number of RSes in at least one RB supporting multiple antenna port transmission; and   receiving a second number of RSes in at least one RB belonging to said second set of resource blocks RBs.   
     
     
         13 . An apparatus for transmitting reference signals in a wireless communication system, in which a reference signal, RS, defines an antenna port, AP, for a transmit node, TN, and said TN is arranged to transmit a multiple of RSes in resource blocks, RBs, supporting multiple antenna port transmission, for which RBs supporting multiple antenna port transmission first and second exclusive sets of RBs, are determined and at least one broadcast channel, BCH, is provided in RBs belonging to said first set of RBs, said transmit node comprising transmit circuitry, and
 processing circuitry arranged for
 transmission of a first number of RSes in at least one RB supporting multiple antenna port transmission; and 
 transmission of a second number of RSes in at least one RB belonging to said second set of RBs. 
   
     
     
         14 . Equipment for receiving one or more reference signals in a wireless communication system, in which a reference signal, RS, defines an antenna port, AP, for a transmit node, TN, and said TN is arranged to transmit a multiple of RSes in resource blocks, RBs, supporting multiple antenna port transmission, for which resource blocks, RBs, supporting multiple antenna port transmission first and second exclusive sets of RBs, are determined and at least one broadcast channel, BCH, is provided in RBs belonging to said first set of RBs, said receive node, RN, being comprising
 receive circuitry, and   processing circuitry arranged for
 reception of a first number of RSes in at least one RB supporting multiple antenna port transmission; and 
 reception of a second number of RSes in at least one RB belonging to said second set of RBs.