Configuration of demodulation reference signals in beamformed wireless communication systems

Abstract

Various embodiments disclosed herein provide for efficient configuration of demodulation reference signals in beamformed wireless communications systems. In an embodiment, the transmitter can signal the location of demodulation reference signals (DMRS) by including an indicator bit in downlink control information indicating which DMRS scheme is used in the transmission. A first DMRS scheme can let the user equipment (UE) device know that the DMRS position for the PDSCH carrying the RMSI is as signaled on the master information block (MIB)—referred to as PDSCH Mapping Type A. A second DMRS scheme can let the UE device know that the DMRS position for the PDSCH carrying the RMSI is the first orthogonal frequency division multiplexing (OFDM) symbol of said PDSCH allocation—referred to as PDSCH mapping type B).

What is claimed is: 
     
         1 . A method, comprising:
 signaling, by network equipment comprising a processor, to a user equipment, a location of a demodulation reference signal in a beamformed transmission comprising remaining system information and a synchronization signal; and   transmitting, by the network equipment, the beamformed transmission in a specified spatial direction.   
     
     
         2 . The method of  claim 1 , wherein signaling the location comprises:
 setting an indicator bit in downlink control information, wherein the indicator bit indicates the location for the demodulation reference signal.   
     
     
         3 . The method of  claim 2 , wherein a setting of the indicator bit indicates that a master information block identifies the location of the demodulation reference signal. 
     
     
         4 . The method of  claim 2 , wherein a setting of the indicator bit indicates that a symbol of a data transport data channel comprises the demodulation reference signal. 
     
     
         5 . The method of  claim 1 , wherein signaling the location comprises:
 employing a symbol index column of a table that indicates the location of the demodulation reference signal.   
     
     
         6 . The method of  claim 1 , wherein signaling the location comprises:
 employing a table that indicates a resource allocation for a data transport data channel in downlink control information, wherein the resource allocation comprises the demodulation reference signal.   
     
     
         7 . The method of  claim 1 , wherein signaling the location comprises:
 indicating, in downlink control information, a resource allocation that comprises the demodulation reference signal.   
     
     
         8 . Network equipment, comprising:
 a processor; and   a memory that stores executable instructions that, when executed by the processor, facilitate performance of operations, comprising:
 identifying, to a user equipment, a symbol that comprises a demodulation reference signal in a beamformed transmission comprising remaining system information and a synchronization signal; and 
 transmitting the beamformed transmission in a defined spatial direction. 
   
     
     
         9 . The network equipment of  claim 8 , wherein identifying the symbol comprises:
 setting an indicator bit in downlink control information, wherein the indicator bit indicates the symbol that comprises the demodulation reference signal.   
     
     
         10 . The network equipment of  claim 9 , wherein a first setting of the indicator bit indicates that a master information block identifies the symbol that comprises the demodulation reference signal. 
     
     
         11 . The network equipment of  claim 10 , wherein the symbol is a first symbol, and wherein a second setting of the indicator bit indicates that a second symbol of a data transport data channel comprises the demodulation reference signal. 
     
     
         12 . The network equipment of  claim 8 , wherein identifying the symbol comprises:
 employing a symbol index column of a table that indicates the symbol that comprises the demodulation reference signal.   
     
     
         13 . The network equipment of  claim 8 , wherein identifying the symbol comprises:
 employing a data structure that indicates a resource allocation for a data transport data channel in downlink control information, wherein the resource allocation comprises the symbol that comprises the demodulation reference signal.   
     
     
         14 . The network equipment of  claim 8 , wherein identifying the symbol comprises:
 indicating, in downlink control information, a resource allocation comprises the symbol that comprises the demodulation reference signal.   
     
     
         15 . A non-transitory machine-readable medium, comprising executable instructions that, when executed by a processor of network equipment, facilitate performance of operations, comprising:
 indicating, to a user equipment, a position of a demodulation reference signal in a beamformed transmission comprising remaining system information and a synchronization signal; and   transmitting the beamformed transmission according to a spatial direction.   
     
     
         16 . The non-transitory machine-readable medium of  claim 15 , wherein indicating the position comprises:
 setting an indicator bit in downlink control information, wherein the indicator bit indicates the position of the demodulation reference signal.   
     
     
         17 . The non-transitory machine-readable medium of  claim 16 , wherein a first setting of the indicator bit indicates that a master information block identifies the position of the demodulation reference signal. 
     
     
         18 . The non-transitory machine-readable medium of  claim 16 , wherein a second setting of the indicator bit indicates that a symbol of a data transport data channel comprises the demodulation reference signal. 
     
     
         19 . The non-transitory machine-readable medium of  claim 15 , wherein indicating the position comprises:
 employing a symbol index column of a table that indicates the position of the demodulation reference signal.   
     
     
         20 . The non-transitory machine-readable medium of  claim 15 , wherein indicating the position comprises:
 employing a table that indicates a resource allocation for a data transport data channel in downlink control information, wherein the resource allocation comprises the demodulation reference signal.