MAC Efficiency Enhancement with ACK/NACK and AGC Pilot Signal Adaptation Mechanism in Millimeter-Wave Communication Systems

Millimeter-wave (mmWave) wireless systems are a focus of great interest for very high data transmission rate in a short range. Considering short-range communication with a range of the order of several tens of centimeters, only terminals present in this communication range will be influenced. In one-to-one communication, a simpler and more efficient access mechanism is required. Current CSMA/CA based MAC has limits to achieve a high data transmission by reasons of the low MAC efficiency, which is caused by a high overhead of signal exchanges, like interframe space (IFS) and acknowledgement. This paper proposes two methods that enhance the MAC efficiency in shortrange one-to-one communication. The ACK/NACK mechanism uses Negative ACK (NACK) as the acknowledgement policy and solves a problem arising from NACK. The automatic gain control (AGC) pilot signal adaptation mechanism adapts the length of the pilot signals for AGC.