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Simulation of ETSI's High Performance Local Area Network Type 2 (HIPERLAN/2) is presented. MATLAB/Simulink modelling demonstrated that for 64-QAM mode, with coding rate 2/3, a data rate of 48 Mbit/s is achieved with 3.2 dB SNR improvement compared to coding rate 3/4 (with puncturing) as required for the maximum 54 Mbit/s.
Introduction: Higher data rates in wireless communication can be achieved by increased, or more efficient use of, bandwidth and transmitting power. A key technique for spectral optimisation is orthogonal frequency division multiplexing (OFDM) [1].The European Telecommunication Standards Institute (ETSI) and IEEE have proposed OFDM for high-speed wireless LAN and it is being considered for 4G mobile. ETSI's proposed HIPERLAN=2standard describes the physical (PHY) layer based on OFDM technology and thedatarateofHIPERLAN=2 ranges from 6 to 54 Mbit=s depending on Quality of Service (QoS). It is designed to provide Wireless Local Loop (WLL) to core networks, e.g. Asynchronous Transfer Mode, GSM=UMTS or any IP-based multimedia network. The link adoption scheme automatically determines the data rate, coding rate and modulation type depending on the channel conditions. In this Letter we present HIPERLAN=2 performance analysis via a MATLAB= Simulink (Version 6.5 Release 13) simulation with standard and nonstandard coding rates.
Theory: In OFDM, high-rate data-streams are split into multiple lower rate streams and transmitted simultaneously using different subcarriers. Individual groups of bits (symbols) modulate mutually orthogonal subcarriers. An inverse fast Fourier transform (IFFT) block converts the frequency domain signals (e.g. QAM symbols) into a time domain signal (sum of sinusoids) and the process is reversed at the receiver. Correlation with every basis function using an FFT determines the energy for each subcarrier. Since subcarriers are uncorrelated their spectra can overlap (enhancing spectral efficiency) without causing intercarrier interference (ICI). Delay spread (DS), the time difference between the first and last reception of the same symbol due to multipath effects in the channel, causes intersymbol interference (ISI). Hence, guard times are required to separate successive OFDM symbols, but contain no information and waste energy. The duration of...