Digital Chunk Processing with Orthogonal GFDM Doubles Wireless Channel Capacity

Abstract

A novel physical layer (PHY) transmission technique for increasing the channel capacity of transmission, termed as Orthogonal Generalized Frequency Division Multiplexing (OGFDM), has been proposed, investigated and evaluated in this paper. A combination of the Digital Hilbert Filter (DHF) with Generalized Frequency Division Multiplexing (GFDM) has been shown to double wireless channel capacity for each transmitted frequency sub-carrier at acceptable Bit Error Rate (BER) limits. By making use of the great properties of Hilbert transforms, orthogonality is achieved between the traditionally non-orthogonal GDFM subcarriers improving the BER and wireless channel capacity of the transmission. The OGFDM seems to combine the attributes of GFDM and Orthogonal Frequency Division Multiplexing (OFDM) in one sustainable system. The proposed solution achieves orthogonality between the filters of adjacent frequencies of subcarriers instead of between the frequencies of subcarriers themselves. Also, an OGFDM system model is presented, based on which, the relation between the main filter parameters and the system BER and channel capacity performance is specified in a wireless electrical back-to-back transmission system. Finally, by means of simulations, the impact of applying the proposed advanced filters on the aggregated system performance of the BER and channel capacity is shown in an Additive White Gaussian Noise (AWGN) wireless channel.

New Multi-Carrier Candidate Waveform For the 5G Physical Layer of Wireless Mobile Networks

“…After the successful trial of employing the orthogonal digital Hilbert filters for the single carrier of the GFDM [16], in this paper, the supportive Hilbert filters are essentially utilized for the multi-carrier level of the most candidate waveform (GFDM). Thus, introducing an advanced design of the OGFDM to achieve extensively the orthogonality for the GFDM from the multi-carrier perspective.…”

“…At the receiver side, where the Hilbert filters are inversely employed for the multi-carrier, the impulse responses of each corresponding pair of the matching filters are expressed as follows [16]:…”

“…To extract the intended signal, the convolution operation is performed between the shaping and matching filters as follows [16]: where t 0 represents the potential delay time, the subscripts i and j state to the position of the f c, and the superscripts C and D refers either in-phase or quadrature-phase stage.…”

“…Very recently, a single carrier candidate waveform termed as Orthogonal Generalized Frequency Division Multiplexing (OGFDM) is proposed [16]. The lately introduced waveform, which is essentially based on the Physical layer (PHY) of the GFDM, has achieved the orthogonality between the unorthogonally filtered subcarriers of a single frequency centre (f c) of the GFDM.…”

“…Consequently, this kind of orthogonality enables to create a new wireless mobile infrastructure can allow the frequencies of subcarriers to be filtered in a dual way. As such, in terms of the single carrier transmission, the utilized OGFDM can double the capacity of transmission in compare to the GFDM [16].…”