METHOD AND APPARATUS FOR DEVICE-TO-DEVICE COMMUNICATION

• US 20150117295A1
• Filed: 10/28/2014
• Published: 04/30/2015
• Est. Priority Date: 10/30/2013
• Status: Abandoned Application

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: YEH, Choongil, AHN, Jae Young
• Application Number:
  US14/525,280
• Publication Number:
  US 20150117295A1
• Time in Patent Office: Days
• US Class Current: 370/312
• CPC Class Codes: H04J 2011/0096 Network synchronisation
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/2692 with preamble design, i.e. with negotiation of the synchronisation sequence with transmitter or sequence linked to the algorithm used at the receiver
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: H04W 76/14 Direct-mode setup
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals

Abstract

A Device-to-Device (D2D) communication method of a first terminal is provided. The first terminal transmits a Physical D2D Broadcasting Channel (PD2DBCH) through a first area of a first frame. The first terminal transmits a signal for D2D synchronization through a second area of the first frame.

Claims

1. A Device-to-Device (D2D) communication method of a first terminal, the communication method comprising:

transmitting a Physical D2D Broadcasting Channel (PD2DBCH) through a first area of a first frame; and

transmitting a signal for D2D synchronization through a second area of the first frame.

2. The communication method of claim 1, wherein the transmitting of a signal for D2D synchronization comprises transmitting a first synchronization signal of signals for the D2D synchronization for at least one of automatic gain control, automatic frequency control, and frame timing acquisition.

3. The communication method of claim 2, further comprising transmitting a Physical D2D Synchronization Channel (PD2DSCH) for the D2D synchronization through the second area.

4. The communication method of claim 3, wherein the transmitting of a PD2DBCH comprises transmitting a first physical signal for automatic gain control and at least one PD2DBCH through each subframe of the first area.

5. The communication method of claim 4, wherein the transmitting of a first physical signal comprises generating the first physical signal using a second Orthogonal Frequency Division Multiplexing (OFDM) symbol having a smaller length than that of a first OFDM symbol used in a Long Term Evolution (LTE) system.

6. The communication method of claim 5, wherein the generating of the first physical signal comprises:

generating a first sequence by inserting zeros into a Zadoff-Chu (ZC) sequence;

generating the second OFDM symbol having a length that is 1/N (N is a natural number of 2 or more) times a length of the first OFDM symbol using the first sequence; and

generating the first physical signal using a continuous plurality of second OFDM symbols.

7. The communication method of claim 6, wherein the transmitting of a first physical signal further comprises transmitting the first physical signal using a frequency that is allocated to the PD2DBCH,

wherein the first physical signal has different values according to a location of a frequency resource that is allocated to the PD2DBCH.

8. The communication method of claim 6, wherein the transmitting of a first physical signal further comprises transmitting the first physical signal using a predesignated frequency regardless of a frequency that is allocated to the PD2DBCH.

9. The communication method of claim 3, wherein the transmitting of a first synchronization signal comprises generating the first synchronization signal using a second OFDM symbol with a smaller length than that of a first OFDM symbol used in an LTE system.

10. The communication method of claim 9, wherein the generating of the first synchronization signal comprises:

generating a first sequence by inserting zeros of (N−

1) (N is a natural number of 2 or more) times a length of a ZC sequence into the ZC sequence;

generating the second OFDM symbol having a length that is 1/N times a length of the first OFDM symbol using the first sequence; and

generating the first synchronization signal using a continuous plurality of second OFDM symbols.

11. The communication method of claim 3, wherein the transmitting of a first synchronization signal comprises:

receiving the first synchronization signal from a second terminal;

acquiring synchronization using the first synchronization signal; and

transmitting the first synchronization signal to a third terminal.

12. The communication method of claim 3, wherein the transmitting of a PD2DBCH comprises transmitting the PD2DBCH that is multiplexed with a Frequency Division Multiplexing (FDM) method in the first area.

13. A Device-to-Device (D2D) communication method of a first terminal, the communication method comprising:

receiving a first synchronization signal for D2D synchronization from a second terminal through a first area of a first frame; and

performing at least one of automatic gain control, automatic frequency control, and frame timing acquisition in a time domain using the first synchronization signal,

wherein the first frame comprises the first area and a second area for a Physical D2D Broadcasting Channel (PD2DBCH).

14. The communication method of claim 13, wherein the first synchronization signal is generated using a second OFDM symbol with a smaller length than that of a first OFDM symbol used in an LTE system.

15. The communication method of claim 14, wherein the performing comprises performing the automatic gain control, the automatic frequency control, and the frame timing acquisition in a time domain using the first synchronization signal before Fast Fourier Transform (FFT) is performed.

16. The communication method of claim 14, wherein the performing comprises performing the frame timing acquisition in a time domain through a matched filter using the first synchronization signal.

17. The communication method of claim 13, further comprising:

transmitting a second synchronization signal for D2D synchronization to the second terminal through the first area to make the second terminal measure propagation delay using the second synchronization signal;

receiving a propagation delay measuring result from the second terminal; and

performing timing adjustment for correction of propagation delay using the propagation delay measuring result.

18. The communication method of claim 17, wherein the transmitting of the second synchronization signal comprises generating the second synchronization signal that the first terminal and the second terminal can commonly use.

19. The communication method of claim 18, wherein the generating of the second synchronization signal comprises:

generating a first sequence using a root sequence of ZC sequences;

generating a Cyclic Prefix (CP), which is ½

of a length of the first sequence; and

generating a Guard Time (GT), which is ½

of a length of the first sequence.

20. A terminal, comprising:

a memory; and

a processor that is connected to the memory and that performs D2D communication,

wherein the processor generates a first synchronization signal for D2D synchronization using a second OFDM symbol with a smaller length than that of a first Orthogonal Frequency Division Multiplexing (OFDM) symbol used in a Long Term Evolution (LTE) system, and transmits the first synchronization signal through a first area of a first frame, and

the first frame comprises the first area and a second area for transmitting/receiving a Physical D2D Broadcasting Channel (PD2DBCH).