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This article studies Large Intelligent Systems (LIS) along with Single Carrier with Frequency Domain Equalization (SC-FDE), utilizing Low-Density Parity-Check (LDPC). Four different receivers are studied in the scenarios described above, namely Equal Gain Combining (EGC), Maximum Ratio Combining (MRC), Zero Forcing (ZF), and Minimum Mean Squared Er...
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Context 1
... LIS systems scenarios, various receiver design strategies are possible. First, linear feedforward non-iterative FDE receivers such as ZF, MMSE, MRC, and EGC, and second, nonlinear feedback equalization iterative MRC and EGC receivers are possible (Figure 2). ...
Citations
... LDPC coding enables a coded MIMO system to attain a data rate that is very close to the Shannon limit. The concurrent processing of many streams is crucial for achieving Gbps wireless transmission [19]. LDPC coding is preferable for Gbps wireless transmission over Turbo coding because of its simplicity in implementation. ...
... , N − 1} defines the mapping between the time domain and frequency domain. Additionally, W k represents the subcarriers' frequency-domain block channel noise [19]. ...
This study investigates receiver design solutions for distributed Massive Multiple Input Multiple Output (D-m MIMO) systems, taking into account parameters such as number of access points as well as concerns related to channel estimates that use single-carrier frequency-domain equalization (SC-FDE). A significant contribution of this research is the integration of Low-Density Parity-Check (LDPC) codes to simplify coding complexity and enhance communication efficiency. The research examines different receiver designs, such as spatial antenna correlation and sophisticated channel estimation methods. The authors propose integrating LDPC codes into the receiver architecture to simplify computations and enhance error correction and decoding. Moreover, the paper examines performance evaluation measures and approaches, highlighting the trade-offs among complexity, spectral efficiency, and error performance. The comparative analysis indicates the benefits, in terms of performance, of incorporating LDPC codes and improving system throughput and dependability. We examine four distinct receiver algorithms: zero-forcing (ZF), minimum mean square error (MMSE), maximum ratio combining (MRC), and equal gain combining (EGC). The study shows that MRC and EGC receivers work well in D-m MIMO because they make the receiver system less computationally demanding.
... In this article, we analyse an LIS [9][10][11][12][13] system associated with a single carrier with frequency domain equalization (SC-FDE) [14,15], which is an alternative to orthogonal frequency division multiplexing (OFDM). Due to the high peak-to-average power ratio (PAPR) of OFDM signals, their use in uplink scenarios is not well suited. ...
... This article is an extension of the research published in [10], using a subset of the antenna LIS elements (referred to as a partial LIS), instead of the whole LIS. Because it is a function of the number of antennas, the computational complexity decreases when using only antenna elements that are closer to the user equipment (UE) instead of the whole LIS. ...
... When LDPC codes are used, these have a code rate of ½. The length of the LPDC codes utilized in the simulations is 32,400 from the DVB-S.2 standard (also used in [10]). LDPC codes have gained significant attention due to their excellent performance in various communication systems, including wireless, satellite, and optical communication. ...
One of the key technologies of 6G communications relies on large intelligent surfaces (LIS), which can be viewed as a near-field beamformer that is supportive of extremely high symbol rates and enables a high level of interference avoidance. This article focuses on LIS systems, analysing the impact of the use of a whole LIS system or a subset of an antenna array. We analyse an LIS system associated with a single carrier with frequency domain equalization (SC-FDE), and with different receiver types of varying complexities. Because it is a function of the number of antennas, the computational complexity decreases when antenna elements that are closer to the user equipment are used instead of the whole LIS. Moreover, with a partial LIS, a reduction of energy consumption is achieved, and mitigation of the interference levels is obtained, allowing a performance very close to that obtained with the whole LIS system.
... In [21], an IRS-assisted CR system was proposed by establishing an optimization to maximize the secrecy rate of ST while a static Eve exists; cooperative beamforming was considered as well, to ensure the quality of service (QoS) of the primary receiver (PR). In addition, the IRS has been exploited to assist secure communication by cooperating with other traditional security technologies such as the AN [22], cooperative relaying [23], and power-transfer SWIPT and simultaneous wireless information [24][25][26]. The author in [27] employed adaptive transmit power along with energy harvesting in CRNs. ...
... We assumed that the SR-TX, the SR, the PR, the Eve, and the IRS were located at (0, 10), (180, 0), (160, 0), (170, 0), and (100, 25) in meters (m) on a two-dimensional plane [3], respectively. The channels of the SR-TX-Eve, SR-TX-SR, and SR-TX-PR experienced Rayleigh fading, while the IRS-SR, SR-TX-IRS, IRS-Eve, and IRS-PR links all experienced Rician fading with a Rician factor of 4. The path loss index from ST to all user links was set to 3, the path loss index from ST to IRS links was set to 2.5, and the path loss index from the IRS to all user links was set to 2.5. ...
Cognitive radio (CR) acts as a significant player in enhancing the spectral efficiency (SE) of wireless telecommunications; simultaneously, the intelligent reflecting surface (IRS) technique is a valid technique for increasing the confidentiality properties of wireless telecommunications systems through the modulation of the amplitude and phase shift of the channel. Therefore, we take into consideration an IRS-assisted multiple-input single-output (MISO) CR system to raise the confidentiality rate, which is composed of a primary network with a primary receiver (PR) and an eavesdropping link, as well as a secondary network with a secondary receiver (SR) and SR transmitter (SR-TX). In particular, we minimize the SR’s transmit power under the interference temperature (IT) and confidentiality capacity constraints via the joint optimization of the beamforming vector and artificial noise (AN) constraint matrix at SR-TX together with the phase shift matrix of IRS. Numerical outcomes indicate that various transmit antenna values and the IRS element numbers at SR-TX can greatly reduce transmit power while assuring secure communication.
