This invention is a transmission device capable of enhancing the reception characteristics of a terminal when employing transmit diversity using two antenna ports in an ePDCCH. In a base station (100) that transmits a reference signal to a terminal (200) using two antenna ports, a setting unit (102), on the basis of the reception quality of the terminal, sets as the aforementioned two antenna ports either a first antenna port pair for which DMRS (reference signals) do not undergo mutual code multiplexing, or a second antenna port pair for which the DMRS do undergo code multiplexing. A transmitter (109) transmits the DMRS from the two antenna ports set in the setting unit (102).

This invention is a transmission device capable of enhancing the reception characteristics of a terminal when employing transmit diversity using two antenna ports in an ePDCCH. In a base station (100) that transmits a reference signal to a terminal (200) using two antenna ports, a setting unit (102), on the basis of the reception quality of the terminal, sets as the aforementioned two antenna ports either a first antenna port pair for which DMRS (reference signals) do not undergo mutual code multiplexing, or a second antenna port pair for which the DMRS do undergo code multiplexing. A transmitter (109) transmits the DMRS from the two antenna ports set in the setting unit (102).

An ultra-low power data transmission method and apparatus are disclosed. An ultra-low power data transmission method to be performed by a user terminal of an ultra-low power data transmission system includes performing channel coding on a payload included in a transmission packet; interleaving a payload obtained through the channel coding, spreading the interleaved payload using a gold code and an orthogonal variable spreading factor (OVSF), combining a synchronization header spread using the gold code and the OVSF with the spread payload, and modulating a transmission packet in which the payload and the synchronization header are combined.

Embodiments of the present invention describe a data transmission method, a related device, and a system. The method may include sending, by a terminal, uplink data to a network device. The uplink data is scrambled by using a scrambling sequence, and the scrambling sequence is generated based on information about a radio resource used by the terminal to send the uplink data. According to the embodiments of the present invention, it can be ensured that scrambling and descrambling on the uplink data are successfully implemented when the network device does not obtain an identifier of the terminal in a cell.

The communication method using an almost periodic function code includes using, for modulation, almost periodic function codes the number of which is in accordance with the number of users or the number of channels, among K almost periodic function codes. Where k is an integer from 1 to K and is an identifier for identifying each of the K almost periodic function codes, a parameter that determines each of the K almost periodic function codes is represented by +(k1)/K. The symbol K is N or 2N, where N is a code length of each almost periodic function code. The symbol is a real number greater than 0 and less than 1/N.

An ultra-low power data transmission method and apparatus are disclosed. An ultra-low power data transmission method to be performed by a user terminal of an ultra-low power data transmission system includes performing channel coding on a payload included in a transmission packet; interleaving a payload obtained through the channel coding, spreading the interleaved payload using a gold code and an orthogonal variable spreading factor (OVSF), combining a synchronization header spread using the gold code and the OVSF with the spread payload, and modulating a transmission packet in which the payload and the synchronization header are combined.

Embodiments of the present invention describe a data transmission method, a related device, and a system. The method may include sending, by a terminal, uplink data to a network device. The uplink data is scrambled by using a scrambling sequence, and the scrambling sequence is generated based on information about a radio resource used by the terminal to send the uplink data. According to the embodiments of the present invention, it can be ensured that scrambling and descrambling on the uplink data are successfully implemented when the network device does not obtain an identifier of the terminal in a cell.

Various examples with respect to generation of reference signals with improved cross-correlation properties in wireless communications are described. A processor of a user equipment (UE) selects a column of a Hadamard matrix to provide a vector and also generates a pseudo-random sequence. The processor scrambles the vector with the pseudo-random sequence to provide a scrambling sequence and performs a cyclic shift on the scrambling sequence to provide a cyclic-shifted scrambling sequence. The processor then generates a reference signal by performing a pi/2-binary phase shift keying (BPSK) modulation on the cyclic-shifted scrambling sequence.

The communication method using an almost periodic function code includes using, for modulation, almost periodic function codes the number of which is in accordance with the number of users or the number of channels, among K almost periodic function codes. Where k is an integer from 1 to K and is an identifier for identifying each of the K almost periodic function codes, a parameter that determines each of the K almost periodic function codes is represented by +(k1)/K. The symbol K is N or 2N, where N is a code length of each almost periodic function code. The symbol is a real number greater than 0 and less than 1/N.