There is a desire to implement multi-cell/sector cooperation (e.g., coordinated multipoint (CoMP)) to provide additional capacity and additional coverage in wireless systems. CoMP, as well as other techniques, is expected to significantly increase available bandwidth in fourth generation (4G) and beyond communications systems. However, CoMP and the other techniques require knowledge of communications channels between transmitter(s) and receiver(s).
Generally, pilot sequences or simply pilots are signals transmitted by a transmission point (TP), such as an enhanced NodeB (eNB), also commonly referred to as a NodeB, base station, communications controller, controller, a cell, a remote radio head (RRH), and the like, to help a receiver, such as a user equipment (UE), also commonly referred to as mobile stations, mobiles, subscribers, terminals, users, and the like, estimate a communications channel between the eNB and the UE. Typically, pilots should be short since communications overhead increases rapidly with pilot length.