An adaptive block pilot scheme for OFDM systems

The inset method, modulation technique and transmit channel of block pilot signal was researched in order to improving the low channel using efficiency which brought by fixation of inset pilot density in traditional OFDM. Therefore an adaptive block pilot scheme with low complexity was proposed in response to a traditional OFDM system with fixed pilot having a lack of channel utilization. It is designed to react to environmental conditions and reduces the overall pilot overhead when ideal performance is guaranteed. Furthermore, placement of pilot signals and signaling to facilitate this adaptive operation were also addressed. Simulation results showed that the proposed scheme remarkably improves system performance with low pilot overhead compared to conventional schemes.