Device to device communication method and apparatus

Abstract

Embodiments of the present invention provide a device to device D2D communication method and apparatus, to resolve at least a problem of a low success rate of discovery between user equipments in the prior art. The method includes: determining, by first user equipment UE, to-be-sent first signaling, where the first signaling includes one or a combination of the following information: a transmission probability, a quantity of retransmission times, a transmission period, a type of a cyclic prefix CP, a transmit power, a current quantity of hops, a quantity of antenna ports, a transmission mode, a bandwidth of a D2D link, a D2D link frame number, time division duplexing TDD uplink and downlink configuration information, or information indicating whether the first UE is within a network; and sending, by the first UE, the first signaling to second UE by using the D2D link.

What is claimed is: 
     
         1 . A device to device (D2D) communication method, the method comprising:
 determining, by a first D2D device, first signaling to be sent, wherein the first signaling comprises one or a combination of the following information: a transmission period, a quantity of antenna ports, a Multiple-Input Multiple-Output (MIMO) transmission mode, time division duplexing (TDD) uplink and downlink configuration information, or information indicating whether the first D2D device is within a network; and   sending, by the first D2D device, the first signaling to a second D2D device using a dedicated control channel in the D2D link;   wherein the dedicated control channel is scrambled by using a scrambling sequence when being generated, wherein the scrambling sequence is used to identify that the dedicated control channel is a channel carrying the first signaling, and an initial value c init  used when the scrambling sequence is generated is an integer not less than 336.   
     
     
         2 . The method according to  claim 1 , wherein the determining, by the first D2D device, the first signaling comprises:
 determining, by the first D2D device, the first signaling according to preconfigured information; or   receiving, by the first D2D device, a signaling from a third D2D device using the D2D link, and determining the first signaling according to the signaling received from the third D2D device; or   receiving, by the first D2D device, a signaling from a base station, and determining the first signaling according to the signaling received from the base station.   
     
     
         3 . The method according to  claim 1 , wherein the information comprised in the first signaling is further used to implicitly indicate second information comprised in the first signaling. 
     
     
         4 . The method according to  claim 1 , further comprising:
 transmitting, by the first D2D device, a D2D synchronization signal in the D2D link, wherein the D2D synchronization signal comprises a primary sidelink synchronization signal (PSSS) and a secondary sidelink synchronization signal (SSSS), wherein sidelink synchronization signal identities (SLSSIDs) that correspond to the PSSS and the SSSS are integers not less than 336, and the SLSSIDs are used to identify a channel carrying the first signaling in the D2D link.   
     
     
         5 . The method according to  claim 1 , wherein the dedicated control channel comprises a reserved field, and some or all bits in the reserved field are used to carry the first signaling. 
     
     
         6 . The method according to  claim 1 , wherein the dedicated control channel further carries second signaling, and the second signaling is used to identify that the dedicated control channel is a channel carrying the first signaling. 
     
     
         7 . The method according to  claim 1 , wherein the dedicated control channel uses a cyclic redundancy check (CRC) mask when being generated, and the CRC mask is used to identify that the dedicated control channel is a channel carrying the first signaling. 
     
     
         8 . The method according to  claim 1 , wherein the sending, by the first D2D device, the first signaling to the second D2D device using the D2D link comprises:
 sending, by the first D2D device, the first signaling to the second D2D device using the D2D link, wherein the first signaling is carried in one or a combination of the following manners:
 a cyclic redundancy check (CRC) mask, a D2D synchronization signal, or a demodulation reference signal (DMRS). 
   
     
     
         9 . The method according to  claim 1 , wherein the initial value used when the scrambling sequence is generated is a value c init  that satisfies:
 c init =nSLSSID, wherein nSLSSID is an integer not less than 336.   
     
     
         10 . A device to device (D2D) device for D2D communication, the D2D device comprising:
 a processor; and   a transmitter,   wherein the processor is configured to determine first signaling to be sent, wherein the first signaling comprises one or a combination of the following information: a transmission period, a quantity of antenna ports, a Multiple-Input Multiple-Output (MIMO) transmission mode, a D2D link frame number, time division duplexing (TDD) uplink and downlink configuration information, or information indicating whether the D2D device is within a network;   wherein the transmitter is configured to send the first signaling to second D2D device using a dedicated control channel in the D2D link; and   wherein the dedicated control channel is scrambled by using a scrambling sequence when being generated, wherein the scrambling sequence is used to identify that the dedicated control channel is a channel carrying the first signaling, and an initial value used when the scrambling sequence is generated is an integer not less than 336.   
     
     
         11 . The D2D device according to  claim 10 , further comprising a receiver, wherein:
 the processor is configured to determine the first signaling according to preconfigured information; or   the receiver is configured to receive signaling from a third D2D device using the D2D link, and the processor is configured to determine the first signaling according to the signaling that is received from the third D2D device and that is received by the receiver; or   the receiver is configured to receive signaling from a base station, and the processor is configured to determine the first signaling according to the signaling received from the base station and that is received by the receiver.   
     
     
         12 . The D2D device according to  claim 10 , wherein the information comprised in the first signaling is further used to implicitly indicate second information comprised in the first signaling. 
     
     
         13 . The D2D device according to  claim 10 , wherein the transmitter is further configured to transmit a D2D synchronization signal in the D2D link, wherein the D2D synchronization signal comprises a primary sidelink synchronization signal (PSSS) and a secondary sidelink synchronization signal (SSSS), wherein sidelink synchronization signal identities (SLSSIDs) that correspond to the PSSS and the SSSS are integers not less than 336, and the SLSSIDs are used to identify a channel carrying the first signaling in the D2D link. 
     
     
         14 . The D2D device according to  claim 10 , wherein the dedicated control channel further carries second signaling, and the second signaling is used to identify that the dedicated control channel is a channel carrying the first signaling. 
     
     
         15 . The D2D device according to  claim 10 , wherein the dedicated control channel uses a cyclic redundancy check (CRC) mask when being generated, and the CRC mask is used to identify that the dedicated control channel is a channel carrying the first signaling. 
     
     
         16 . The D2D device according to  claim 10 , wherein the first signaling is carried in one or a combination of the following manners: a cyclic redundancy check (CRC) mask, a D2D synchronization signal, or a demodulation reference signal (DMRS). 
     
     
         17 . The D2D device according to  claim 10 , wherein the initial value used when the scrambling sequence is generated is a value c init  that satisfies:
 c init =nSLSSID, wherein nSLSSID is an integer not less than 336.