Читать книгу Wireless Connectivity - Petar Popovski - Страница 20

The problem of first contact becomes easier if the mobile devices are equipped with full-duplex capability. If Zoya and Yoshi both transmit simultaneously an invite packet to each other, then each of them will simultaneously receive the invite packet from the other device. Furthermore, in the next slot both Zoya and Yoshi transmit an invitation_accepted packet and, again, Zoya receives this packet from Yoshi and vice versa. With this, the link can be considered as being established. Therefore, full-duplex avoids the need for randomized assignment of transmit/receive roles and thus speeds up the procedure of link establishment. This may appear to be one of the most important advantages of full-duplex technology in scenarios in which fast link establishment and device discovery is of high importance.

We note that, even with full-duplex, there is still the problem of interference due to collision. Hence, full-duplex cannot help to solve the problem of colliding invite packets in Figure 1.3, as Zoya still does not get either of the two invite packets.