One of the main drawbacks of MIMO-OFDM systems
is that the transmitted signals may have a high PAPR.
Many PAPR reduction techniques have been presented for
MIMO-OFDM systems [16]-[20]. The conventional PTS
scheme, as shown in Fig. 1, applied directly to each of the
transmitting antennas of the MIMO-OFDM system, is referred
to as the ordinary PTS (oPTS) scheme. The oPTS scheme has
a good PAPR reduction performance, but it suffers from high
computational complexity. In the cooperative PTS (co-PTS)
scheme presented in [20], the authors use alternate optimization
to reduce the number of multiplications of rotation factors
and use spatial subblock circular permutations between antennas
to increase the number of candidate signals. Both the oPTS
and co-PTS methods show a good PAPR reduction performance
for MIMO-OFDM systems; however, they use all the
samples to estimate the peak power of candidate signals in the
optimization process.