Summary: IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 18, NO. 7, JULY 2000 1169
A Differential Detection Scheme for
Vahid Tarokh, Member, IEEE, and Hamid Jafarkhani, Member, IEEE
Abstract--We present a transmission scheme for exploiting di-
versity given by two transmit antennas when neither the trans-
mitter nor the receiver has access to channel state information. The
new detection scheme can use equal energy constellations and en-
coding is simple. At the receiver, decoding is achieved with low de-
coding complexity. The transmission provides full spatial diversity
and requires no channel state side information at the receiver. The
scheme can be considered as the extension of differential detection
schemes to two transmit antennas.
Index Terms--Antenna arrays, differential detection, space-time
codes, transmitter diversity.
IN THE past few years, significant progress in code design
for transmitter diversity over the wireless channel has been
made. The primary focus was on the case when only the receiver
knows the channel, which is the case for most practical systems.