A diagram of the transmitter and the receiver based on the above considerations is provided in Figure 2. The multiband approach that permits obtaining high data rate transmissions is illustrated. From the functional blocks shown in transmitter and receiver diagrams, it can be seen that each block can exploit state-of-theart low cost and low-power analog technology for the front end. Digital conversion and processing requirements for SDR section are also standard.

General Points

The asynchronous approach relaxes constraints to simplify hardware implementation. Primarily, only a coarse synchronization is needed (an error of 2 ns << Ti ' 40 ns is acceptable), which makes the system robust against the clock jitter and every triggering inaccuracy. Secondly, because the processing is based on energy, the transceiver performances are nearly insensitive to distortion and phase non-linearities of devices like antennas, amplifiers or filters.
Finally, low-power consumption is achieved, thanks to the use of mainly analog and passive devices.