Method for uplink transmission in unlicensed band, and device using same
A method and a device for uplink transmission in an unlicensed band are provided. The device receives an uplink grant for uplink transmission in an unlicensed band from a base station, and transmits an uplink channel in a subframe in the unlicensed band on the basis of the uplink grant. The subframe comprises a plurality of orthogonal frequency division multiplexing(OFDM) symbols, and at least one of a plurality of the OFDM symbols is defined by gaps during which the uplink channel is not transmitted.
1. A method for uplink (UL) transmission in an unlicensed band, the method comprising:
receiving, by a wireless device, a UL grant for physical uplink shared channel (PUSCH) transmission in the unlicensed band from a base station (BS),
wherein the UL grant comprises resource allocation of consecutive UL subframes for the PUSCH transmission and further comprises information related to an initial portion of the PUSCH transmission in the consecutive UL subframes, wherein an initial orthogonal frequency division multiplexing (OFDM) symbol or a part of the initial OFDM symbol in an initial subframe of the consecutive UL subframes is configured to be empty based on the information of the UL grant; and
transmitting, by the wireless device, a PUSCH in the consecutive UL subframes of the unlicensed band based on the UL grant,
wherein each UL subframe comprises a plurality of OFDM symbols.
2. The UL transmission method of claim 1 , wherein the wireless device or another wireless device performs clear channel assessment (CCA) based on the UL grant.
3. The UL transmission method of claim 1 , wherein the UL grant further comprises information related to whether clear channel assessment (CCA) will be performed for transmission of the PUSCH.
4. The UL transmission method of claim 1 , wherein the PUSCH is transmitted via a secondary cell which is anchored by a primary cell.
5. An apparatus for uplink (UL) transmission in an unlicensed band, the apparatus comprising:
a transceiver configured to transmit and receive radio signals; and
a processor operatively coupled to the transceiver and configured to:
instruct the transceiver to receive a UL grant for physical uplink shared channel (PUSCH) transmission in the unlicensed band from a base station (BS),
wherein the UL grant comprises resource allocation of consecutive UL subframes for the PUSCH transmission and further comprises information related to an initial portion of the PUSCH transmission in the consecutive UL subframes, wherein an initial orthogonal frequency division multiplexing (OFDM) symbol or a part of the initial OFDM symbol in an initial subframe of the consecutive UL subframes is configured to be empty based on the information of the UL grant; and
instruct the transceiver to transmit a PUSCH in the consecutive UL subframes of the unlicensed band based on the UL grant,
wherein each UL subframe comprises a plurality of OFDM symbols.
6. The apparatus of claim 5 , wherein the apparatus or another apparatus performs clear channel assessment (CCA) based on the UL grant.
7. The apparatus of claim 5 , wherein the PUSCH is transmitted via a secondary cell which is anchored by a primary cell.