A communication apparatus of the present disclosure includes a receiver which, in operation, receives a signal that includes a non-legacy preamble and a data field, the non-legacy preamble comprising a first field for indicating a number of spatial streams (Nss) in the data field and a second field for indicating one of a plurality of modulation and coding schemes (MCSs), wherein two or more frequency diversity transmission schemes are supported and one of the two or more frequency diversity transmission schemes is applied based on a value of the Nss; and circuitry which, in operation, decodes the signal.

A method of configuring a preamble of a downlink frame for synchronization in data frame transmission of a 60 GHz wireless local area network system, the method comprising arranging a short preamble having a plurality of repetitive S symbols, and an IS symbol, and arranging a long preamble having a long cyclic prefix (CP) and a plurality of L symbols for frame synchronization and symbol timing by performing auto-correlation according to the length of window of the auto-correlation.

Method of scrambling signals, transmission point device, and user equipment using the method are provided. The method includes: sending an ID table to a user equipment through higher layer signaling, the ID table being a subset of the whole ID space and containing available IDs for the user equipment; notifying the user equipment an ID in the ID table to be used through physical layer signaling or UE specific higher layer signaling; generating a random seed based on the notified ID; initializing a scrambling sequence by the random seed; and scrambling the signals with the initialized scrambling sequence. The method of the disclosure, by combining physical layer signaling and higher layer signaling, may notify the used group ID and the blind detection space to a UE, wherein the blind detection for the UE is enabled and the signaling overhead is reduced.

One embodiment of the present specification provides a method by which a machine type communication (MTC) device configured to operate only in some bands among the system bands of a cell transmits a demodulation reference signal (DMRS) for the demodulation of uplink data. The method can comprise the steps of: selecting any one DMRS sequence among a plurality of sets of DMRS sequences having a length M according to a group hopping number and allocation area information of a sub-physical resource block (PRB), when an uplink signal is transmitted through the sub-PRB including the M number of subcarriers which is less than twelve subcarriers; and mapping the selected DMRS sequence on the M number of subcarriers of the sub-PRB, and transmitting the same.

A method for generating a physical layer (PHY) data unit includes generating a first signal field to include multiple copies of first signal field content, wherein the first signal field content spans one sub-band of a plurality of sub-bands of the PHY data unit, and wherein the multiple copies collectively span the plurality of sub-bands of the PHY data unit; generating a second signal field to include multiple copies of second signal field content, wherein the second signal field content spans multiple ones of the plurality of sub-bands of the PHY data unit, and wherein the multiple copies of the second signal field collectively span the plurality of sub-bands of the PHY data unit; generating a preamble of the PHY data unit to include at least the first signal field and the second signal field; generating the PHY data unit to include at least the preamble.

A synchronization method, an apparatus, and a system, which relate to the communications field and applied to synchronization signal transmission to implement synchronization of data frame transmission between devices on an unlicensed carrier are provided. The synchronization method is applied to synchronization on an unlicensed carrier. A network device sets a synchronization signal in a first subframe, and the network device sends the first subframe or the first subframe and a second subframe to user equipment, where the first subframe includes M orthogonal frequency division multiplexing (OFDM) symbols, the second subframe includes N OFDM symbols, M and N are positive integers, M>N, and the first subframe and the second subframe are subframes of an unlicensed carrier.

Processing and transmitting transmission frames. A method for processing a transmission frame, includes receiving a transmission frame including a bootstrap portion, a preamble portion, and a payload portion. The boot strap portion of the received transmission frame is processed, by processing circuitry of a reception apparatus, to extract preamble structure information from one of four bootstrap symbols included in the bootstrap portion. The preamble portion of the transmission frame is decoded, by the processing circuitry, based on the extracted preamble structure information. A first one of the four bootstrap symbols is used for synchronization and a last one of the four bootstrap symbols in the bootstrap portion includes the preamble structure information. Further, the preamble structure information indicates a structure of one or more preamble symbols in the preamble portion that follows the last symbol.

This disclosure provides methods, devices and systems for increasing the transmit power of wireless communication devices operating on power spectral density (PSD)-limited wireless channels. Some implementations more specifically relate to LTF designs that support distributed transmissions. In some aspects, a transmitting device may obtain a sequence of values representing an LTF of a PPDU and may map the sequence of values to a number (N) of noncontiguous subcarrier indices of a plurality of subcarrier indices spanning a wireless channel according to a distributed tone plan. In some implementations, the transmitting device may modulate the sequence of values on N tones, representing a logical RU, and map the N tones to the N noncontiguous subcarrier indices, respectively. In some other implementations, the sequence of values may be obtained based on relative locations of the N noncontiguous subcarrier indices in the wireless channel.

A network controller may configure one or more channel state information-reference signal (CSI-RS) configurations for transmitting RSs to user equipments (UEs) for tracking. A CSI-RS configuration may specify a set of CSI-RS resources for transmitting RSs in two consecutive slots. The set of CSI-RS resources may include a plurality of one-port CSI-RS resources configured according to the CSI-RS configuration. The CSI-RS configuration may specify a quasi co-location (QCL) configuration including a set of QCL parameters, where a demodulation reference signal (DMRS) has a QCL relationship with the RS with respect to the set of QCL parameters. The network controller may signal the one or more CSI-RS configurations to UEs.

A terminal and a storage medium are provided. The storage medium stores a program for causing a processor to implement a method performed by the terminal, the method includes: sending, to a network device, first indication information which is used to indicate, to the network device, at least one of: number of first SRS resource sets required by the terminal, number of first SRS resources in a first SRS resource set, maximum layer number of uplink multi-antenna transmission of the terminal, whether uplink transmission channels of the terminal are coherent, and maximum number of PTRS ports supported for uplink transmission by the terminal, and is used by the network device to determine second indication information used to instruct the terminal to send an SRS signal; receiving second indication information sent by the network device; sending an SRS signal according to second indication information.