In-room transmission BER performance of anti-multipath modulation PSK-VP

The BER (bit error rate) performance of an anti-multipath modulation π/4-QPSK-VP is evaluated in comparison to a conventional differential π/4-QPSK, when applied to high-speed digital radio transmission within a room where both transmitting and receiving antennas are set up, using a transmission experiment and a BER calculation. Through this transmission experiment at about 3 and 6 Mb/s, π/4-QPSK-VP was confirmed to improve the BER significantly for both data rates in two test rooms. A delay profile measurement was additionally carried out to characterize the propagation channels of the test rooms and to find out an appropriate channel model. The BER calculation based on the above channel model, which was confirmed to estimate the upper bound of a floor error rate sufficiently in comparison to the transmission experiment, reveals the relationship between the data rate and the BER and indicates an optimum and a maximum data rate for π/4-QPSK-VP with respect to the maximum delay spread of the room. The results show that π/4-QPSK-VP is estimated to raise the available data rate up to about 20 times over that of π/4-QPSK for a BER of 10^-4, although π/4-APSK-VP requires twice the transmission bandwidth