A Pragmatic Design of Frequency-Domain Equalizers for Offset Modulations

Offset modulations such as OQPSK (Off- set Quaternary Phase Shift Keying) and OQAM (Offset Quadrature Amplitude Modulation), combined with SC- FDE (Single-Carrier with Frequency-Domain Equalization) are an interesting choice for broadband wireless systems, that require low-complexity transmitters and efficient power amplification. However, the FDE perfor- mance can be rather poor due to interference between the in-phase and quadrature components at the sampling instants, especially when large constellations are employed. In this paper we propose pragmatic iterative and non- iterative FDE designs for offset modulations. Our performance results show that both iterative and non-iterative pragmatic FDE receivers have excellent performance, even for large OQAM constellations.