We address the problem of blind carrier frequency-offset (CFO) estimation in quadrature amplitude modulation,
phase-shift keying, and pulse amplitude modulation
communications systems.We study the performance of a standard
CFO estimate, which consists of first raising the received signal to
the Mth power, where M is an integer depending on the type and
size of the symbol constellation, and then applying the nonlinear
least squares (NLLS) estimation approach. At low signal-to noise
ratio (snr), the NLLS method fails to provide an accurate CFO
estimate because of the presence of outliers. In this letter, we derive
an approximate closed-form expression for the outlier probability.
This enables us to predict the mean-square error (MSE) on CFO
estimation for all snr values. For a given snr, the new results
also give insight into the minimum number of samples required in
the CFO estimation procedure, in order to ensure that the MSE
on estimation is not significantly affected by the outliers.
標簽：
frequency-offset
estimation
quadrature
amplitude
上傳時間：
2014-01-22
上傳用戶：牛布牛
基于OFDM的無線寬帶系統(tǒng)仿真It contains mainly two parts, i.e. link-level simulator and system-level simulator.
Link-level simulator focus on a single-cell single-user scenario, where signal is transmitted from tx, and estimated at rx. Comparing the difference in tx/rx signal, the error rate can be found out. The output of the link-level simulator is the BLER/BER vs. snr mapping table, that can be used for the system-level simulation.
System-level simulator focus on a multi-cell multi-user scenario. For the sake of simplicity, it takes the mapping table aquired in the link-level simulation, measure the actural snr, and finds the corresponding error rate.
標簽：
simulator
i.e.
system-level
link-level
上傳時間：
2016-03-15
上傳用戶：xsnjzljj
