OFDM Enhancements for 5G Based on Filtering and Windowing

In this chapter, different variants envisioned for the 5G new radio (NR) waveform implementation are discussed, satisfying the 5G NR requirements for release 15 and beyond. We outline the limitations of conventional CP-OFDM in serving the potential use cases for NR. Two main classes of waveform preprocessing are considered to increase the spectral decay rate of CP-OFDM, namely windowing and filtering. Three waveforms are selected for the comparison, namely windowed overlap-add (WOLA) as a windowing technique, universal filtered orthogonal frequency division multiplex (UF-OFDM) and filtered orthogonal frequency division multiplex (f-OFDM) as subband filtering techniques. We outline the design principles of all three waveforms and discuss the overall performance and implementation aspects.

[1]  Behrouz Farhang-Boroujeny,et al.  OFDM Versus Filter Bank Multicarrier , 2011, IEEE Signal Processing Magazine.

[2]  Gilberto Berardinelli,et al.  Zero-tail DFT-spread-OFDM signals , 2013, 2013 IEEE Globecom Workshops (GC Wkshps).

[3]  Gerhard Fettweis,et al.  A Reduced Complexity Time-Domain Transmitter for UF-OFDM , 2016, 2016 IEEE 83rd Vehicular Technology Conference (VTC Spring).

[4]  H. Tullberg,et al.  The Foundation of the Mobile and Wireless Communications System for 2020 and Beyond: Challenges, Enablers and Technology Solutions , 2013, 2013 IEEE 77th Vehicular Technology Conference (VTC Spring).

[5]  Ming Jia,et al.  Filtered OFDM: A new waveform for future wireless systems , 2015, 2015 IEEE 16th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC).

[6]  Reinaldo A. Valenzuela,et al.  OFDM for 5G: Cyclic prefix versus zero postfix, and filtering versus windowing , 2016, 2016 IEEE International Conference on Communications (ICC).

[7]  Xi Zhang,et al.  Filtered-OFDM - Enabler for Flexible Waveform in the 5th Generation Cellular Networks , 2014, 2015 IEEE Global Communications Conference (GLOBECOM).

[8]  Frank Schaich,et al.  Subcarrier spacing - a neglected degree of freedom? , 2015, 2015 IEEE 16th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC).

[9]  Mikko Valkama,et al.  Efficient Fast-Convolution Implementation of Filtered CP-OFDM Waveform Processing for 5G , 2015, 2015 IEEE Globecom Workshops (GC Wkshps).

[10]  Frank Schaich,et al.  Pilot-Aided Channel Estimation for Universal Filtered Multi-Carrier , 2015, 2015 IEEE 82nd Vehicular Technology Conference (VTC2015-Fall).

[11]  Frank Schaich,et al.  Multiple Access and Waveforms for 5G: IDMA and Universal Filtered Multi-Carrier , 2014, 2014 IEEE 79th Vehicular Technology Conference (VTC Spring).

[12]  Mikko Valkama,et al.  Efficient Fast-Convolution-Based Waveform Processing for 5G Physical Layer , 2017, IEEE Journal on Selected Areas in Communications.

[13]  Erik Dahlman,et al.  Background of LTE , 2011 .

[14]  Frank Schaich,et al.  Relaxed synchronization support of universal filtered multi-carrier including autonomous timing advance , 2014, 2014 11th International Symposium on Wireless Communications Systems (ISWCS).

[15]  Mikko Valkama,et al.  Optimized fast convolution based filtered-OFDM processing for 5G , 2017, 2017 European Conference on Networks and Communications (EuCNC).

[16]  Frank Schaich,et al.  Coexistence of UF-OFDM and CP-OFDM , 2016, 2016 IEEE 83rd Vehicular Technology Conference (VTC Spring).

[17]  Stephen B. Weinstein,et al.  The history of orthogonal frequency-division multiplexing [History of Communications] , 2009, IEEE Communications Magazine.

[18]  Erik Dahlman,et al.  4G: LTE/LTE-Advanced for Mobile Broadband , 2011 .

[19]  Frank Schaich,et al.  Waveform Contenders for 5G - Suitability for Short Packet and Low Latency Transmissions , 2014, 2014 IEEE 79th Vehicular Technology Conference (VTC Spring).

[20]  R. Chang.  Synthesis of band-limited orthogonal signals for multichannel data transmission , 1966 .

[21]  Frank Schaich,et al.  5GNOW: non-orthogonal, asynchronous waveforms for future mobile applications , 2014, IEEE Communications Magazine.