Evaluation of SC-FDMA Physical Link Using USRP
01 Jan 2021-pp 1003-1017
TL;DR: SC-FDMA link has been modeled and proposed to design this link using LabVIEW and the simulation results show that the PAPR and BER parameters of the proposed SC- FDMA link design are significantly lower than the OFDMA in downlink.
Abstract: Single-Carrier Frequency Division Multiple-Access (SC-FDMA) is used in uplink data transmission in Long-Term Evaluation (LTE) due to its low Peak-to-Average Power Ratio (PAPR) properties. In this paper, SC-FDMA link has been modeled and proposed to design this link using LabVIEW. The real-time data transmission through the SC-FDMA link is carried out using Software Defined Radio (SDR) testbed which is implemented using Universal Software Radio Peripheral (USRP) devices. The data transmission and reception are carried out through SC-FDMA link and the performance evaluation is estimated for PAPR and Bit Error Rate (BER). The simulation results show that the PAPR and BER parameters of the proposed SC-FDMA link design are significantly lower than the OFDMA in downlink. Moreover, the simulation of BER with different modulation schemes is carried out for different Signal to Noise Ratio (SNR) values. The analysis of PAPR impacts the OFDMA waveform and benefits on SC-FDMA transmission link in any channel condition.
Citations
More filters
••
TL;DR: In this article, an iterative heuristic optimal resource allocation (HORA) algorithm and a chunk based resource block allocation (CRBA) scheduling algorithm were proposed to determine resource block (RB) allocation among users to satisfy the quality of service requirement.
Abstract: Long Term Evolution—Advanced (LTE-A) is the most widely used and encouraging technology for 4G and 5G mobile networks. The LTE technology in wireless networks has achieved a significantly high throughput because it makes use of multiple access schemes. We propose an iterative heuristic optimal resource allocation (HORA) algorithm and a chunk based resource block allocation (CRBA) scheduling algorithm to determine resource block (RB) allocation among users to satisfy the quality of service requirement. A heuristic approach which is used in HORA offers a tradeoff between computational complexity and performance. It performs RB and power allocation separately to reduce computational complexity. In the CRBA algorithm sets of RBs are allocated to groups of users keeping power constant to all users. User selection is performed based on channel conditions to improve throughput. RB allocation is an additive method to maximize the data transmission rate and energy efficiency. The use of channel quality indicator feedback from the user equipment (UE) to eNodeB plays an important role in the selection of appropriate modulation and coding schemes and benefits the assigned chunk of RBs to users in the wideband channel-dependent selective frequency-time domain. Here, RB usage and quality-of-service (QoS) constraint are considered for the scheduling algorithm. The HORA algorithm assigns most RBs to users who have high-value signal to noise ratio and continues the RB allocation until it meets the QoS criteria of all users in consideration of the threshold value of the power budget. Problems that arise during continuous resource allocation to the scheduled user are considered as APX-hard and NP-hard problems. An RB and power allocation optimization problem is formulated for the maximum data rate in the cellular network. The simulation results show that the proposed approaches demonstrate considerable throughput improvement at the user end in a significant and robust condition.
2 citations
••
06 Jul 2021TL;DR: In this article, a cross-tier interference is addressed in the two-tier 5G architecture, where a massive MIMO is used at the base stations (BSs) which served micro user equipment (MUEs).
Abstract: 3GPP standard is exploring the enhancement of 5G development. As a result, a more durable network must be created to enable huge access to networks and intelligent communication systems beyond 5G and 6G. In this paper, a cross-tier interference is addressed in the two-tier 5G architecture. A massive MIMO is used at the Base stations (BSs) which served micro user equipment (MUEs)., and small cells (SBSs) are equipped with lesser antennas are served to small cell user equipment (SUEs). A synchronized co-channel TDD is used to communicate over the available bandwidth. The advantage of the synchronized co-channel TDD mode is utilized to estimate the channel. A correlation matrix of a received signal is estimated from the uplink (UL) pilot signal. Hence we modified the correlation matrix and therefore even though the precise knowledge of the interfering channel is not available the channel can be estimated. A modified heuristic optimal resource allocation (HORA) algorithm is used for scheduling. The simulation demonstrates considerable throughput improvement at the user end in two-tier cellular architecture and robust conditions.
••
12 Apr 2021
TL;DR: The authors have requested that this preprint be removed from Research Square.
Abstract:
The authors have requested that this preprint be removed from Research Square.
••
TL;DR: In this paper , the authors proposed a multiuser uplink scheduler based on recursive maximum expansion (RME) algorithm to assign resource blocks (RBs) to active users in an optimum manner to improve the system's spectral efficiency.
Abstract: 5G architecture allows the use of new radio alongside long‐term evolution‐A (LTE‐Advanced) and enables cellular mobile networks to handle extraordinarily high traffic volume data. The major challenge in current uplink data transmission systems is making resource blocks (RBs) available in a continuous form and assigning them to active users in an optimum manner to improve the system's spectral efficiency. The best N‐subset (BNS) minimization technique is suggested to identify the best of the best continuous chunks of RBs from the existing system bandwidth, followed by a modified recursive maximum expansion (RME) algorithm to assign RBs to users in the most optimal manner. The algorithm together is referred to as a multiuser uplink scheduler BNSRME algorithm. A constraint utility maximization problem is formulated to allocate RBs to UEs in the most optimized manner. Utility matrix is then converted into a weighted sum‐rate maximization problem allowing weights to be updated adaptively based on marginal utility values. In addition, a threshold limit is considered based on the signal‐to‐noise ratio in the BNSRME‐TH algorithm, which satisfies multiusers in terms of assigned resources and improves system performance, spectral efficiency, and throughput. This MU scheduling strategy is used in the 5G uplink non‐stand‐alone cellular network. The findings exhibit that the proposed multiuser algorithm increases system spectral efficiency by 31.65% in comparison with the existing opportunistic algorithms. It has been observed that the performance of the system is further increased by using the MU‐MIMO framework.
References
More filters
••
TL;DR: It is shown by simulations that the proposed probabilistic pulse shaping method achieves considerable improvements over the conventional SC-FDMA system in terms of both PAPR and bit-error-rate (BER) performance with low additional complexity.
Abstract: To avoid the excess bandwidth and noise enhancement penalty involved in the pulse-shaping method for peak-to-average power ratio (PAPR) reduction of single-carrier frequency-division multiple access (SC-FDMA) signals, we propose a novel alternative method, which is called probabilistic pulse shaping . A set of weighting windows with zero excess bandwidth is designed to weight the outputs of the discrete Fourier transform precoder of a block of SC-FDMA symbols in a slot. Then, the candidate signal blocks with different weighting windows for each block are generated with the designed low-complexity implementation scheme, and the signal block with the lowest PAPR is selected to be transmitted. At the receiver, the received data can be detected in the same way as that of the conventional SC-FDMA using the defined equivalent channel without side information. It is shown by simulations that the proposed method achieves considerable improvements over the conventional SC-FDMA system in terms of both PAPR and bit-error-rate (BER) performance with low additional complexity.
28 citations
••
TL;DR: This work designs and implements a network-coded cooperation (NCC) system that operates in real time through the use of software-defined radio (SDR) nodes for the first time in the literature and shows that the NCC-OFDMA system can significantly improve the communication quality and robustness, while enabling data transmission between multiple users.
Abstract: Benefits of network coding towards enhancing communication quality, both in terms of robustness or data transmission rates, make it a significant candidate as a future networking technology. Conventionally, network coding is mostly used in wired infrastructures, where transmission errors between nodes are negligible. Capturing the provided benefits of network coding via straightforward extension from wired networks to wireless networks is not trivial. In addition to the challenges introduced through the wireless channel impairments, we can also capture the spatial diversity gain provided by the broadcast nature of the wireless channels. In this work, we design and implement a network-coded cooperation (NCC) system that operates in real time through the use of software-defined radio (SDR) nodes for the first time in the literature. We specifically target wireless networks. Our system is based on orthogonal frequency division multiple access (OFDMA) that provides a practical means to enable high transmission rates through the use of narrowband subcarriers. The developed testbed is composed of three source nodes, a relay node and two destination nodes. The transmission of the proposed NCC-OFDMA system is completed in two phases; the broadcast and the relaying phases. Multiplexing of source nodes’ signals is achieved through OFDMA technique. In the broadcast phase, an OFDMA signal is transmitted to relay and destination nodes. In the relaying phase, the relay node first detects the OFDMA signal, generates network-coded symbols, and then transmits these symbols to destination nodes. At the end of these two phases, the destination nodes determine the source nodes’ signals by using network decoders. The destination nodes make use of both the uncoded and network-coded symbols, which are received in broadcast and relaying phases, respectively. Destination nodes then perform network decoding. Through real-time bit error rate and error vector magnitude measurements, we show that the NCC-OFDMA system can significantly improve the communication quality and robustness, while enabling data transmission between multiple users, as known from theoretical analyses. Some features of this implemented NCC-OFDMA system have the potential to be included in 5G standards, due to the improved radio resource usage efficiency.
16 citations
••
TL;DR: A new transceiver architecture design for the uplink SC-FDMA system that implements a cosine basis function or a complex exponential Fourier basis function and the proposed architecture uses the discrete wavelet transform and a hybrid companding and clipping method for peak-to-average power ratio reduction.
Abstract: In this paper, the discrete cosine transform (DCT) is utilized for single carrier frequency division multiple access (SC-FDMA) transmission Firstly, an improved DCT-based SC-FDMA (DCT SC-FDMA) system is introduced Then, the paper presents a new transceiver architecture design for the uplink SC-FDMA system that implements a cosine basis function or a complex exponential Fourier basis function The proposed architecture uses the discrete wavelet transform and a hybrid companding and clipping method for peak-to-average power ratio (PAPR) reduction From the simulation results, it is shown that the DCT SC-FDMA system achieves a superior bit error rate (BER) performance than that of the discrete Fourier transform based SC-FDMA (DFT SC-FDMA) system The results also show that the proposed wavelet based transceiver architectures for the DFT SC-FDMA system and the DCT SC-FDMA system can provide a better BER performance and a lower PAPR than the conventional DFT SC-FDMA system
11 citations
••
18 Nov 2011TL;DR: An AWGN channel model is derived for SC-FDMA transmission, which is useful for benchmarking experimental results and compared to theoretical and simulated performance.
Abstract: In this paper we discuss the implementation of a Single Carrier Frequency Division Multiple Access (SC-FDMA) transceiver running over the Universal Software Radio Peripheral 2 (USRP2). SC-FDMA is the air interface which has been selected for the uplink in the latest Long Term Evolution (LTE) standard. In this paper we derive an AWGN channel model for SC-FDMA transmission, which is useful for benchmarking experimental results. In our implementation, we deal with signal scaling, equalization and partial synchronization to realize SC-FDMA transmission over a noisy channel at rates up to 5.184 Mbit/s. Experimental results on the Bit Error Rate (BER) versus Signal-to-Noise Ratio (SNR) are presented and compared to theoretical and simulated performance.
9 citations
••
01 Nov 2017TL;DR: From the analysis, the space-time-frequency block coding (STFBC) shows better performance in both MIMO SCFDMA systems and can improve the performance of BER and PAPR about 42% and 47% with diversity technique.
Abstract: The multiple-input-multiple-output (MIMO) concept and orthogonal frequency division multiple access (OFDMA) combination has been perceived as the most auspicious system to attain high transmission data rate and mitigate inter-symbol interference (ISI). However, high peak-to-average power ratio (PAPR) in OFDMA causes non-linearity at the receiving end of the system. Thus, single carrier frequency division multiple access (SCFDMA) technology is used to compensate this issue. This study evaluates the performance of both OFDMA and SCFDMA system based on the bit error rate (BER) and PAPR values. A comparison of space-time (ST), space-frequency (SF), and space-time-frequency (STF) block coding has been conducted for both systems to achieve better system performance. The best diversity scheme to implement in OFDMA and SCFDMA system in order to minimize PAPR and BER were investigated. From the analysis, the space-time-frequency block coding (STFBC) shows better performance in both MIMO SCFDMA systems. The result obtained that the SCFDMA system can improve the performance of BER and PAPR about 42% and 47% with diversity technique.
9 citations