Abstract
This letter derives the probability distribution function (PDF) of received symbols for orthogonal frequency-division multiplexing (OFDM) based massive multiple-input, multiple-output (MMIMO) systems, which uses maximal-ratio combining (MRC) detection. The effects of noise and interferences are evaluated through random variables, and the PDF is then derived from their joint probability and characteristic functions. The bit error rate (BER) using Binary and Quadrature Phase Shift Keying (BPSK, QPSK), and M-ary Quadrature Amplitude Modulation (QAM) waveforms is then analyzed by using this PDF. Simulation and analytical results confirm that the derived equations provided accurate PDF and BER, and therefore, can be used efficiently to evaluate performance of OFDM-MMIMO systems.
Highlights
MMIMO systems have been widely utilized in wireless networks to enhance their spectral and energy efficiencies [1]
Since the number of transmit and receive antennas in MMIMO system is very large, linear detection has been the focus in a plethora of research works due to its reduced computational complexity compared to non-linear detection
The zero forcing (ZF) operation in Neumann series expansion (NSE) was limited to the first order term and Gram matrix was assumed to be a diagonal matrix
Summary
MMIMO systems have been widely utilized in wireless networks to enhance their spectral and energy efficiencies [1]. This letter introduces a different approach to derive the PDF of received symbols for a multi-user OFDM-MMIMO system utilizing MRC detection and Gray-coded M-QAM modulation. Hn ∈ CNr×Nt is channel frequency response matrix with components, Hi, j, that are complex-valued, zero-mean, Gaussian random variables, that is, CN (0, 2σh ). Hn ∈ CNr×Nt is channel frequency response matrix with components, Hi, j, that are complex-valued, zero-mean, Gaussian random variables, that is, CN (0, 2σh2 ) Their variance per dimension σh is 0.5. Definition of random variables: Undoubtedly, the second and third term in (8) represent the effect of co-channel interferences and enhanced noise in the received symbols for MRC detection. We proceed with the derivation of the PDF of the received symbol for MRC detection, where utilize M-QAM modulation.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have