RATE DETERMINATION IN HIGH EFFICIENCY WIRELESS LAN
The present disclosure relates to a method and apparatus for determining a transmission rate in a Wireless Local Area Network (WLAN). According to one aspect of the present disclosure, a method for receiving an uplink frame from a Station (STA) by an Access Point (AP) in a WLAN may be provided. The method may include transmitting to the STA a downlink frame eliciting the uplink frame, and receiving the uplink frame from the STA at a rate determined based on whether the type of the uplink frame is a single user type or a multi-user type.
1 . A method of facilitating wireless communication, the method comprising:
transmitting, to one or more stations, a plurality of code maps;
transmitting, to the one or more stations, a downlink frame eliciting one or more uplink frames from the one or more stations;
processing a first uplink frame from the one or more stations, the first uplink frame having a first coding rate determined based on a first code map of the plurality of code maps when the downlink frame elicits the first uplink frame for single-user transmission; and
processing a second uplink frame from the one or more stations, the second uplink frame having a second coding rate determined based on a second code map of the plurality of code maps when the downlink frame elicits the second uplink frame for multi-user transmission.
2 . The method of claim 1 , wherein the second code map includes a plurality of subfields, wherein the plurality of subfields respectively corresponds to a plurality of spatial stream numbers, and each of the plurality of subfields indicates a maximum Modulation and Coding Scheme (MCS) for a corresponding spatial stream number.
3 . The method of claim 1 , wherein the processing the second uplink frame from the one or more stations comprises:
receiving multiple uplink frames from the one or more stations, each uplink frame having the second coding rate determined so that lengths of the multiple uplink frames are equal to each other.
4 . The method of claim 1 , wherein when the downlink frame elicits the second uplink frame, processing multiple uplink frames from the one or more stations, wherein coding rates of the multiple uplink frames are equal to each other.
5 . The method of claim 1 , wherein the processing the one or more uplink frames from the one or more stations comprises:
when the downlink frame elicits the first uplink frame, receiving a single uplink frame having a coding rate determined based on a coding rate of the downlink frame and Basic Service Set (BSS) basic rate set information.
6 . The method of claim 5 , wherein the processing the one or more uplink frames from the one or more stations comprises:
when the downlink frame elicits the first uplink frame, receiving a single uplink frame having a highest coding rate of the BSS basic rate set information, equal to or lower than the coding rate of the downlink frame.
7 . The method of claim 5 , wherein the processing the one or more uplink frames from the one or more stations comprises:
when the downlink frame elicits the first uplink frame, receiving a single uplink frame having a coding rate determined further based on Modulation and Coding Scheme (MCS) and Number of Spatial Streams (NSS) set information supported for transmission of the single uplink frame, and information about a number of encoders supported for transmission of the single uplink frame.
8 . The method of claim 1 , wherein the downlink frame is a trigger frame including scheduling information for transmission of the one or more uplink frames.
9 . The method of claim 1 , wherein the downlink frame is a data frame and the one or more uplink frames are control response frames.
10 . The method of claim 1 , wherein the processing the one or more uplink frames from the one or more stations comprises:
when the downlink frame elicits the second uplink frame, receiving multiple uplink frames, each uplink frame having a coding rate determined based on one or more of information about a coding rate or Modulation and Coding Scheme (MCS) limit on transmission of the multiple uplink frames, a rate of the downlink frame, BSS basic rate set information, MCS and NSS set information supported for transmission of the multiple uplink frames, information about a number of encoders supported for transmission of the multiple uplink frames.
11 . A method of facilitating wireless communication, the method comprising:
receiving, from an access point (AP), a plurality of code maps;
receiving, from the AP, a downlink frame eliciting one or more uplink frames;
generating an uplink frame with a first coding rate based on a first code map of the plurality of code maps when the downlink frame elicits an uplink frame for single-user transmission;
generating the uplink frame with a second coding rate based on a second code map of the plurality of code maps when the downlink frame elicits the uplink frame for multi-user transmission; and
providing, for transmission, the uplink frame to the AP.
12 . The method of claim 11 , wherein the second code map includes a plurality of subfields, wherein the plurality of subfields respectively corresponds to a plurality of spatial stream numbers, and each sub-field indicates a maximum Modulation and Coding Scheme (MCS) for a corresponding spatial stream number.
13 . The method of claim 11 , wherein, when the downlink frame elicits multiple uplink frames, the second coding rate is determined so that lengths of the multiple uplink frames are equal to each other.
14 . The method of claim 11 , wherein, when the downlink frame elicits multiple uplink frames, the second coding rate is determined so that coding rates of the multiple uplink frames are equal to each other.
15 . The method of claim 11 , wherein, when the downlink frame elicits a single uplink frame, the first coding rate is determined based on a coding rate of the downlink frame and Basic Service Set (BSS) basic rate set information.
16 . The method of claim 15 , wherein, when the downlink frame elicits the single uplink frame, the first coding rate is determined as a highest coding rate of the BSS basic rate set information, equal to or less than the coding rate of the downlink frame.
17 . The method of claim 15 , wherein, when the downlink frame elicits the single uplink frame, the first coding rate is determined further based on Modulation and Coding Scheme (MCS) and Number of Spatial Streams (NSS) set information supported for transmission of the single uplink frame, information about a number of encoders supported for transmission of the single uplink frame.
18 . The method of claim 11 , wherein the downlink frame is a trigger frame including scheduling information for transmission of the one or more uplink frames.
19 . The method of claim 11 , wherein the downlink frame is a data frame and the one or more uplink frames are control response frames.
20 . The method of claim 19 , wherein, when the downlink frame elicits multiple uplink frames, the second coding rate is determined based on one or more of information about a coding rate or Modulation and Coding Scheme (MCS) limit on transmission of the multiple uplink frames, a coding rate of the downlink frame, BSS basic rate set information, MCS and NSS set information supported for transmission of the multiple uplink frames, information about a number of encoders supported for transmission of the multiple uplink frames.