Design of Multi-channel Access Control Scheme for Overlapped Bands

Abstract

In wireless communication, an access control mechanism is especially important to realize a stable connection. Typical access control mechanisms assume a single wireless channel, where every terminal can communicate with each other on the same frequency channel. On the contrary, the industrial, scientific and medical (ISM) radio band using 2.4 GHz has a different assumption for them because the IEEE 802.11 standard assigned each channel for 5 MHz, but conventional devices transmit a 20 MHz band signal. As a result, an overlapped band may be interference to a signal over a neighbor channel. This paper proposes a new type of access control mechanism supporting multichannel. The proposed scheme employs a different bandwidth signal for access control and data transmission. As a result, terminals over neighbor channels can recognize a data transmission even if they cannot demodulate a data transmission signal. The benefit of the proposed scheme is multiple transmission of the access control message over different channels. Since the receiver should receive multiple channels for access control and data transmission, this paper designs an extended system model of Orthogonal Frequency Division Multiplexing (OFDM). The evaluation results show that the proposed scheme can avoid packet conflicts between neighbor channels.