Power saving method in wireless lan system for permitting terminal station to promptly transition to doze state by transmitting empty data frame

Abstract

A power saving method in a wireless LAN system is disclosed for permitting a terminal station to promptly transition to a doze state irrespective of the presence or absence of data destined to the terminal station in a base station. Upon receipt of a PS-Poll signal from a terminal station subordinate to a base station for prompting a transmission of data destined to the terminal station, the base station transmits an ACK signal to the terminal station for indicating a successful reception of the PS-Poll signal. Further, the base station transmits a data frame including data destined to the terminal station when there is such data, or transmits an empty data frame when there is no data destined to the terminal station. Then, upon receipt of the data frame (including the empty data frame), the terminal station transmits an ACK signal to the base station, and then transitions to the doze state in which a transmission/reception function is made inoperative.

1 . A power saving method in a wireless LAN system, comprising the steps of:
 upon receipt of a signal at a base station from a terminal station subordinate to said base station for prompting a transmission of data destined to said terminal station, transmitting an ACK signal indicative of a successful reception of said signal to said terminal station, and transmitting a data frame including data destined to said terminal station when there is such data, and transmitting an empty data frame when there is no data destined to said terminal station; and   upon receipt of the empty data frame at said terminal station, transitioning to a state in which a transmission/reception function is made inactive.   
   
   
       2 . A base station in a wireless LAN system including a terminal station which, upon receipt of an empty data frame at said terminal station, transitions to a state in which a transmission/reception function is made inactive, said base station comprising:
 means responsive to a signal from a terminal station subordinate to said base station for prompting a transmission of data destined to said terminal station, for transmitting an ACK signal indicative of a successful reception of said signal to said terminal station; and   means responsive to the signal received from said terminal station for prompting a transmission of data destined to said terminal station, for generating and transmitting to said terminal station a data frame including data destined to said terminal station when there is such data, and for generating and transmitting to said terminal station an empty data frame when there is no data destined to said terminal station.   
   
   
       3 . A terminal station in a wireless LAN system, comprising:
 first means for transmitting a signal to a base station to which said terminal station is subordinate, for prompting a transmission of data destined to said terminal station; and   second means responsive to an empty data frame received from said base station, for transmitting an ACK signal to said base station and bringing said terminal station into a state in which a transmission/reception function is made inoperative.   
   
   
       4 . A power saving method in a wireless LAN system including a terminal station which, upon receipt of an empty data frame at said terminal station, transitions to a state in which a transmission/reception function is made inactive, and a base station, said method comprising the steps of:
 upon receipt of a signal from a terminal station subordinate to said base station for prompting a transmission of data destined to said terminal station, transmitting an ACK signal indicative of a successful reception of said signal to said terminal station; and   upon receipt of the signal received from said terminal station for prompting a transmission of data destined to said terminal station, generating and transmitting to said terminal station a data frame including data destined to said terminal station when there is such data, and for generating and transmitting to said terminal station an empty data frame when there is no data destined to said terminal station.   
   
   
       5 . A power saving method in a terminal station of a wireless LAN system, said method comprising the steps of:
 transmitting a signal to a base station to which said terminal station is subordinate for prompting a transmission of data destined to said terminal station, and   upon receipt of an empty data frame from said base station at said terminal station, transmitting an ACK signal to said base station, and bringing said terminal station into a state in which a transmission/reception function is made inoperative.   
   
   
       6 . A wireless LAN system comprising: at lease a base station and a terminal station:
 said base station including:   means responsive to a signal from a terminal station subordinate to said base station for prompting a transmission of data destined to said terminal station, for transmitting an ACK signal indicative of a successful reception of said signal to said terminal station; and   means responsive to the signal received from said terminal station for prompting a transmission of data destined to said terminal station, for generating and transmitting to said terminal station a data frame including data destined to said terminal station when there is such data, and for generating and transmitting to said terminal station an empty data frame when there is no data destined to said terminal station,   said terminal station including:   means for transmitting a signal to a base station to which said terminal station is subordinate, for prompting a transmission of data destined to said terminal station; and   means responsive to the empty data frame received from said base station for transmitting an ACK signal to said base station and bringing said terminal station into a state in which a transmission/reception function is made inoperative.