Index Modulation Assisted DCT-OFDM with Enhanced Transceiver Design

An index modulation (IM) assisted Discrete Cosine Transform based Orthogonal Frequency Division Multiplexing (DCT-OFDM) with Enhanced Transmitter Design (termed as EDCT-OFDM-IM) is proposed. It amalgamates the concept of Discrete Cosine Transform assisted Orthogonal Frequency Division Multiplexing (DCT-OFDM) and Index Modulation (IM) to exploit the design freedom provided by the double number of available subcarrier under the same bandwidth. In the proposed EDCT-OFDM-IM scheme, the maximum likelihood (ML) detector used for symbol bits and index bits recovering is derived and the sophisticated designing guidelines for EDCT-OFDM-IM are provided. Based on the derived pairwise error event probability, a theoretical upper bound on the average bit-error probability (ABEP) of EDCT-OFDM-IM is provided over multipath fading channels. Furthermore, the maximum peak-to-average power ratio (PAPR) of our proposed EDCT-OFDM-IM scheme is derived and compared to than the general Discrete Fourier Transform (DFT) based OFDM-IM counterpart

Comparative study of selected subcarrier index modulation OFDM schemes

Orthogonal frequency division multiplexing with subcarrier index modulation (SIM-OFDM) is recently proposed to enhance the performance of traditional OFDM. By incorporating the index modulation in OFDM, the data can be sent on the indices of subcarriers as well as the subcarriers themselves reducing the system complexity. In addition, the Peak to Average Power Ratio (PAPR) and Inter Carrier Interference (ICI) can be reduced by switching on /off some OFDM subcarriers in OOK fashion. In this paper, a comparative study of OFDM with SIM_OFDM and Enhanced SIM_OFDM methods in terms of complexity, spectral efficiency and bit error rate over AWGN channel using two power policies is presented. The simulation results showed that at bit error rate of 10-3, SIM_OFDM and ESIM_OFDM achieved gains in Eb/No of 1.1 dB and 2 dB over 4-QAM OFDM respectively under power reallocation policy. However, the results also showed that traditional OFDM has better spectral efficiency compared to both SIM_OFDM and ESIM_OFDM especially at high M-ary orders

Improving the chromatic dispersion tolerance in long-haul fibre links using the coherent optical orthogonal frequency division multiplexing

Numerical simulations of the coherent optical orthogonal frequency division multiplexing modems are undertaken to investigate the effect of the adaptive modulation, the number of sub-carriers, the cyclic prefix (CP) length, the clipping ratio, quantisation bit resolution and the sampling speed of analogue-to-digital converters (ADCs) on the chromatic dispersion (CD) of a single mode fibre (SMF) at data rates up to 80 Gbps. The use of a large number of sub-carriers is more effective in combating fibre dispersion than employing a long CP; moreover, the optimum number of sub-carriers in the presence of both SMF non-linearities and CD has been identified. The authors show that using a high bit resolution ADC with a high clipping ratio, the transmission distance can be increased at specific data rates. Furthermore, it is shown that ADCs with a low sampling speed also improve the system tolerance to the fibre CD. In addition, simulation results show that the use of adaptive modulation schemes improves spectrum usage efficiency, thus resulting in higher tolerance to the CD when compared with the case in which identical modulation formats are adopted across all sub-carriers

Physical Uplink Control Channel Design for 5G New Radio

The next generation wireless communication system, 5G, or New Radio (NR) will provide access to information and sharing of data anywhere, anytime by various users and applications with diverse multi-dimensional requirements. Physical Uplink Control Channel (PUCCH), which is mainly utilized to convey Uplink Control Information (UCI), is a fundamental building component to enable NR system. Compared to Long Term Evolution (LTE), more flexible PUCCH structure is specified in NR, aiming to support diverse applications and use cases. This paper describes the design principles of various NR PUCCH formats and the underlying physical structures. Further, extensive simulation results are presented to explain the considerations behind the NR PUCCH design.Comment: 6 pages, 11 figures, accepted in IEEE 5G World Forum 201