Power Modulation
Subcarrier power modulation is a type of modulation technique used in some wireless communication systems. It is a method of controlling the power of individual subcarriers in a multiple-carrier system, such as an Orthogonal Frequency Division Multiplexing (OFDM) system. This technique is used to improve the quality of the signal and increase the capacity of the system. It is also used to create a more efficient use of the available spectrum.
With the emergence of new applications (eg, extended reality [XR] and haptics), which require to be simultaneously served not just with low latency and sufficient reliability, but also with high spectral efficiency, future networks (ie, 6G and beyond) should be capable of meeting this demand by introducing new effective transmission designs. Motivated by this, a novel modulation technique termed as orthogonal frequency division multiplexing with subcarrier power modulation (OFDM-SPM) is proposed for providing highly spectral-efficient data transmission with low-latency and less-complexity for future 6G wireless communication systems. OFDM-SPM utilizes the power of subcarriers in OFDM blocks as a third dimension to convey extra information bits while reducing both complexity and latency compared to conventional schemes. In this article, the concept of OFDM-SPM is introduced and its validity as a future adopted modulation technique is investigated over a wireless multipath Rayleigh fading channel. The proposed system structure is explained, an analytical expression of the bit error rate (BER) is derived, and numerical simulations of BER and throughput performances of OFDM-SPM are carried out. OFDM-SPM is found to greatly enhance the spectral efficiency where it is capable of doubling it. In addition, OFDM-SPM introduces negligible complexity to the system, does not exhibit error propagation, reduces the transmission delay, and decreases the transmission power by half.
J. M. Hamamreh, Abdulwahab Hajar, and Mohamedou Abewa, "Orthogonal Frequency Division Multiplexing With Subcarrier Power Modulation for Doubling the Spectral Efficiency of 6G and Beyond Networks." in Transactions on Emerging Telecommunications Technologies, 2020, 1(1). https://doi.org/10.1002/ett.3921 \\
Hajar, A., & Hamamreh, J. M. (2020). The Generalization of Orthogonal Frequency Division Multiplexing With Subcarrier Power Modulation to Quadrature Signal Constellations. RS Open Journal on Innovative Communication Technologies, 1(1). https://doi.org/10.21428/03d8ffbd.4948e89e
Abewa, M., & Hamamreh, J. M. (2021). NC-OFDM-SPM: A Two-Dimensional Non-Coherent Modulation Scheme for Achieving the Coherent Performance of OFDM along with Sending an Additional Data-stream. RS Open Journal on Innovative Communication Technologies, 2(3). https://doi.org/10.46470/03d8ffbd.a97a5236
Abewa, M., & Hamamreh, J. M. (2020). Non-coherent OFDM-Subcarrier Power Modulation for Low Complexity and High Throughput IoT Applications. RS Open Journal on Innovative Communication Technologies, 1(1). https://doi.org/10.46470/03d8ffbd.2a45a9a1
Hijazi, M., & Hamamreh, J. M. (2021). Convolutional Neural Network Based Equalizer for Improving the Reliability Performance of OFDM with Subcarrier Power Modulation. RS Open Journal on Innovative Communication Technologies, 2(5). https://doi.org/10.46470/03d8ffbd.48b1d1c8
Hijazi, M., & Hamamreh, J. M. (2021). Convolutional Neural Network Based Equalizer for Improving the Reliability Performance of OFDM with Subcarrier Power Modulation. RS Open Journal on Innovative Communication Technologies, 2(5). https://doi.org/10.46470/03d8ffbd.48b1d1c8
Abuqamar, A., & Hamamreh, J. M. (2021). Back Propagation Artificial Neural Network for Improving the Performance of STBC-based OFDM with Subcarrier Power Modulation. RS Open Journal on Innovative Communication Technologies, 2(4). https://doi.org/10.46470/03d8ffbd.7aff4a62
Abuqamar, A., Hamamreh, J. M., & Abewa, M. (2021). STBC-assisted OFDM with Subcarrier Power Modulation. RS Open Journal on Innovative Communication Technologies, 2(4). https://doi.org/10.46470/03d8ffbd.275ae770
========