A Collision-Protected Multihop Frame Transmission Method with Wireless LAN Communication Supported by Longer-Distance Wireless Communication

Currently, in addition to wireless LAN (WLAN), equipments for longer-distance wireless communication like IEEE 802.11af and 802.11ah are being developed. Thus, in the near future, access points (APs) and wireless stations (STAs) equipped with functions for both WLAN communication and longer-distance communication are expected. Although longer-distance communication enables STAs to connect to their APs even outside the WLAN coverages, the transmission rates are smaller. Multihop WLAN communication via relay STAs provides larger transmission rates. However, frame transmission from relay STAs increases collisions, and additional routing is required. This study proposes collision-protected multihop transmission without preliminary routing in the environment in which both WLAN communication and longer-distance communication are available. Collision protection and routing are processed by a two-way handshake between data frame transmitter and receiver stations with the longer-distance communication. After the handshake, the data frame is transmitted via relay STAs by exclusively using the WLAN channel.