Sung Ho Cho

SEP performance of coherent MPSK over fading channels in the presence of phase/quadrature error and I-Q gain mismatch

This letter presents a joint approach to the symbol-error probability (SEP) of coherent M-ary phase-shift keying in a situation where the phase error, quadrature error, and in-phase-quadrature (I-Q) gain mismatch problems take place all concurrently over an additive white Gaussian noise and arbitrary fading channel. A set of equations that characterizes the conditional SEP on an instantaneous fading signal-to-noise ratio is derived in the form of the Craig representation.

Probability of an arbitrary wedge-shaped region of the MPSK system in the presence of quadrature error

The paper presents a new and simple expression for computing the probability on an arbitrary wedge-shaped region between two different phase angles when the signal vector is perturbed by two-dimensional Gaussian noise in the presence of a quadrature error. The two-dimensional Gaussian Q-function is used to characterize the expression. The expression can be very useful for computing the analytical error probability of the M-ary phase shift keying system operating in various channel environments.

Effect of the phase error, quadrature error, and I-Q gain mismatch on symbol error probability for an M-PSK system in fading channels

This paper investigates the average symbol error probability (SEP) performance of the coherent M-ary phase shift keying (M-PSK) system in a situation where the phase error, quadrature error, and I-Q gain mismatch problems take place all concurrently over an additive white Gaussian noise (AWGN) and Nakagami-m fading channel. An analytical expression for the average SEP is derived. Computer simulation results are included based on our analysis in order to examine the overall SEP performance of the M-PSK system for various combinations of the phase error, quadrature error, and I-Q gain mismatch values.

Downlink blocking probability in the handover region for uncoordinated WCDMA and cdma2000 systems

The downlink blocking probability of uncoordinated WCDMA and cdma2000 systems for the worst-case scenario is investigated. The analytical expression for the downlink blocking probability is derived using the lower bound approximation. A fairly large set of experiments is performed in order to: (1) investigate the behavior of the frequency dependent rejection ratio for different values of the guard band, (2) demonstrate the validity of analytical results, (3) examine the downlink blocking probability for different values of the distance between the dominant interfering base stations and the victim mobile station, and finally (4) explore the co-sited downlink blocking probability for different values of the guard band.