There is currently much interest in the development of Optic Wireless and Visible Light Communication (VLC) systems in the ITS field. Research in VLC and boomerang systems in particular often remain at a theoretical or computer-simulated level. This paper reports the 3-stage development of a boomerang prototype communication and ranging system using visible light V2V communication via LEDs and photodiodes, with direct-sequence spread spectrum techniques. The system uses simple and widely available components aiming for a low-cost frugal innovation approach. Results show that while we have to improve the prototype distance measurement unit due to a margin of error, simultaneous communication and ranging is possible with our newly designed prototype. The benefits of further research and development of boomerang technology prototypes are confirmed.

This paper proposes a novel cooperative scheme combining distributed space-time block code (STBC) at physical layer, multiple access protocol at medium access control (MAC) layer and opportunistic routing without complicated routing algorithm for achieving high reliability for vehicle-to-vehicle (V2V) communications. The proposed scheme can reduce interference and collision, and achieve reducing redundant broadcast of safety-related messages for multi-hop vehicular communications on highway. In particular, we propose a novel algorithm of relay selection based-on position, speed and direction of movement to select intermediate vehicle stations (VS) with high contribution according to the transmission direction. Furthermore, in order to reduce interference and collision, we install a new timer to select a master relay vehicle station (MVS) which manages a packet transmission of whole network to trigger and synchronize transmitting timing of relay VSs (RVSs) in each hop. From the results of simulations, we can confirm that the proposed method can achieve reducing the redundant broadcast safety-related messages with keeping the packet loss probability by limiting the retransmission at each VS.