Download now Free registration required
Guard Time length (GT) is one of the key OFDM parameters. It is implemented as Cyclic Prefix (CP) to completely alleviate InterSymbol Interference (ISI) and to preserve orthogonality among OFDM subcarriers as long as the guard time length is sufficiently greater than channel delay spread. Conventional OFDM system uses a large GT length to tolerate worst case channel condition irrespective of its current state. This technique, however, degrades the overall spectral efficiency as well as consumes transmitter energy proportional to the length of the guard time. In this paper, the authors optimize the guard time length for mobile WiMAX system over ITU-R M.1225 multipath fading channel. The overall system performance and resultant Packet Error Rate (PER) are slightly improved as function of the guard time length.
- Format: PDF
- Size: 303.3 KB