Patent ID: 7675892

Claim:
A sub-access point (AP) which adjusts the power of a transmission signal, the sub-AP comprising: a reception unit which receives a beacon frame and a data frame from a main AP; a received signal strength indicator (RSSI) checking unit which identifies an RSSI of the main AP with reference to the received beacon frame or the received data frame; a frame error rate (FER) checking unit which identifies an FER from the received data frame; a calculation unit which calculates a median RSSI and a median FER of the main AP; and a control unit which determines a transmission level at which a transmission signal is to be transmitted based on the median RSSI and the median FER, and which causes a transmission signal to be output with a power level equivalent to the determined transmission level, wherein the control unit examines a service set identifier (SSID) of the main AP with reference to the received beacon frame or the received data frame, and the RSSI checking unit, the FER checking unit, the calculation unit, and the control unit operate only if the control unit determines, based on the examination, that the SSID of the main AP is the same as a SSID of the sub-AP.