Upgrading Physical Layer of Multi-Carrier OGFDM Waveform for Improving Wireless Channel Capacity of 5G Mobile Networks and Beyond

On the brink of sophisticated generations of mobile starting with the fifth-generation (5G) and moving on to the future mobile technologies, the necessity for developing the wireless telecommunications waveform is extremely required. The main reason beyond this is to support the future digital lifestyle that tends principally to maximize wireless channel capacity and number of connected users. In this paper, the upgraded design of the multi-carrier orthogonal generalized frequency division multiplexing (OGFDM) that aims to enlarge the number of mobile subscribers yet sustaining each one with a high transmission capacity is presented, explored, and evaluated. The expanded multi-carrier OGFDM can improve the performance of the future wireless network that targets equally the broad sharing operation (scalability) and elevated transmission rate. From a spectrum perspective, the upgraded OGFDM can manipulate the side effect of the increased number of network subscribers on the transmission bit-rate for each frequency subcarrier. This primarily can be achieved by utilizing the developed OGFDM features, like acceleration ability, filter orthogonality, interference avoidance, subcarrier scalability, and flexible bit loading. Consequently, the introduced OGFDM can supply lower latency, better BW efficiency, higher robustness, wider sharing, and more resilient bit loading than the current waveform. To highlight the main advantages of the proposed OGFDM, the system performance is compared with the initial design of the multicarrier OGFDM side by side with the 5G waveform generalized frequency division multiplexing (GFDM). The experimented results show that by moving from both the conventional OGFDM and GFDM with 4 GHz to the advanced OGFDM with 6 GHz, the gained channel capacity is improved. Because of the efficient use of Hilbert filters and improved rate of sampling acceleration, the upgraded system can gain about 3 dB and 1.5 dB increments in relative to the OGFDM and GFDM respectively. This, as a result, can maximize mainly the overall channel capacity of the enhanced OGFDM, which in turn can raise the bit-rate of each user in the mobile network. In addition, by employing the OGFDM with the dual oversampling, the achieved channel capacity in worst transmission condition is increased to around six and twelve times relative to the OGFDM and GFDM with the normal oversampling. Furthermore, applying the promoted OGFDM with the adaptive modulation comes up with maximizing the overall channel capacity up to around 1.66 dB and 3.32 dB compared to the initial OGFDM and GFDM respectively. A MATLAB simulation is applied to evaluate the transmission performance in terms of the channel capacity and the bit error rate (BER) in an electrical back-to-back wireless transmission system

Orthogonal Generalized Frequency Division Multiplexing (OGFDM)

This thesis focuses on introducing a novel technique of the transmission waveform termed as orthogonal generalized frequency division multiplexing (OGFDM) for increasing the wireless channel capacity without the need for extra bandwidth (BW) size or power consumption. The new wireless waveform (OGFDM) tends to obtain a better BW efficiency which in turn can increase highly the wireless channel capacity in comparison with the generalized frequency division multiplexing (GFDM) and cyclic-prefix orthogonal frequency division multiplexing (CP-OFDM). The main feature of the OGFDM is developing the physical layer of future mobile networks by achieving the orthogonality between non-orthogonal filters, removing the interference between adjacent frequency subcarriers, and gaining a flexible bit loading scheme. Since the key downsides of the 4G waveform (CP-OFDM), several alternative transmission waveforms have been investigated for improving transmission techniques of the upcoming communication networks (5G and beyond). This, as a result, comes up with introducing the GFDM as the best candidate waveform for the 5G air interface. Nevertheless, due to ignoring the orthogonality with the GFDM, the BW efficiency is severely affected which in turn causes in extremely reducing the gained channel capacity (research gap). For this reason, the proposed OGFDM waveform aims to improve wireless channel capacity by investigating different levels of processing and carrier schemes. As such, three key levels called as filtration level, oversampling level, and modulation level are adopted for a variant range of OGFDM carriers like a single carrier, couple carrier, quadruple carrier, and multi-carrier system. Regarding the single carrier OGFDM system where the filtration level is developed, the orthogonality is attained between the non-orthogonal filters of the GFDM frequency subcarriers. The core idea behind this novel technique is increasing the efficiency of the applied BW which in turn can double the capacity of the channel at the acceptable level of the bit error rate (BER). Concerning the couple carrier OGFDM system where the oversampling level is developed, the double oversampling mode is applied side by side with the normal one. As a result, the OGFDM waveform can efficiently avoid the interference between adjacent frequency subcarriers improving the quality of service under bad transmission states. As regards the quadruple carrier OGFDM system where the modulation level is improved, a flexible modulation scheme is utilized rather than the fixed modulation formats. Consequently, multilevel modulation shapes are optimally assigned to gain an enhanced channel capacity in accordance with the realistic transmission state. To achieve a higher BW efficiency, the preliminary multi-carrier system that combines the three levels of processing in one uniformed physical platform is introduced. To demonstrate the main advantages of OGFDM waveform, the multicarrier system is further extended and compared with the GFDM (5G technology) and CP-OFDM (LTE Ericsson technology). Hence, the multi-carrier OGFDM can double, boost, and yet maximize the bit-rate of the transmission relative to the GFDM and CP-OFDM at the acceptable level of the BER. The MATLAB simulation and Visio tools are utilized to validate the results and represent them graphically