Inter-subcarrier Interference Research Articles

On Optimally Shaped Signals for Nonlinear Frequency Division Multiplexed Fiber Systems

An approximated channel model is proposed for direct signaling on the continuous spectrum of a nonlinear frequency division multiplexed (NFDM) communication system, describing the effect of noise and nonlinearity at the receiver. The optimal input distribution that maximizes the mutual information of the proposed approximated channel under the peak amplitude constraint is then studied. We present that, considering the input-dependency of the noise, the conventional amplitude-constrained constellation designs can be geometrically shaped to provide significant mutual information gains. However, it is observed that further probabilistic shaping and constellation size optimization can provide only limited additional gains beyond the best geometrically shaped benchmark scheme, i.e., 64 Amplitude Phase Shift Keying. Then, an approximated channel model that neglects the correlation between subcarriers is proposed for the matched filtered signaling system, based on which the input constellation is geometrically shaped. We demonstrate that although the inter-subcarrier interference in the filtered case is neglected in the channel model, the shaping of the matched filtered case can provide promising gains in mismatch capacity over the unfiltered scenario.

Deep Learning-Assisted OFDM Channel Estimation and Signal Detection Technology

The orthogonal frequency division multiplexing (OFDM) technique has received wide attention because of its high spectrum utilization. However, the drawback of inter-subcarrier interference in OFDM systems makes the channel estimation and signal detection performance of OFDM systems with few pilots and short cyclic prefixes (CP) poor. In this paper, we use deep learning to assist OFDM in recovering nonlinearly distorted transmission data. Specifically, we use a self-normalizing network (SNN) for channel estimation, combined with a convolutional neural network (CNN) and a bidirectional gated recurrent unit (BiGRU) for signal detection, thus proposing a novel SNN-CNN-BiGRU network structure (SCBiGNet). The simulation results show that the SCBiGNet model outperforms the existing techniques for the different numbers of pilots and lengths of CPs. The BER performance is improved by 0.2~9 dB.

Self-Interference-Resistant IEEE 802.11ad-Based Joint Communication and Automotive Radar Design

The IEEE 802.11ad based joint communication and radar sensing (JCRS) has attracted great attention for vehicles in recent years. Existing studies mostly assume full-duplex radio for radar receiver based on perfect self-interference cancellation. However, the self-interference may not be fully cancelled in practice. In this paper, imperfect self-interference cancellation is considered. To combat the strong self-interference, a novel JCRS is developed based on IEEE 802.11ad orthogonal frequency division multiplex physical-layer (OFDM PHY) for multi-target sensing. More specifically, the received radar signal is designed to be synchronized with self-interference, and two radar sensing functions are developed for short-range sensing and long-range sensing separately. The synchronization with self-interference resolves the difficulty in self-interference calibration in short-range sensing and prevents the inter-subcarrier-interference (ICI) from self-interference in long-range sensing. The Golay sequences in the preamble are leveraged to combat self-interference for short-range sensing, thanks to the relatively strong reflection signal. For long-range sensing, the pilot signal and a few self-interference-free OFDM symbols at the end of the data frame are leveraged to combat self-interference. Particularly, a novel pilot signal design is first developed to achieve subcarrier-wise pulse radar for accurate velocity and coarse range estimation, and then the self-interference-free OFDM symbols are utilized to achieve accurate range estimation. A strategy of frame transmissions is finally developed to integrate these two functions while balancing the performance between communications and sensing. Simulation results show that cm/s level velocity estimation and cm level range estimation can be achieved for up to 200-meter radar sensing.

Human opinion dynamics optimization for ICI mitigation in MC-CDMA systems

This paper presents a novel social impact based approach named as Human Opinion Dynamics Optimization (HODO) to detect signals of Multi-Carrier Code Division Multiple Access (MC-CDMA) systems in the presence of Inter Subcarrier Interference (ICI). The ICI occurs because of various factors, such as Carrier Frequency Offset (CFO), Sampling Frequency Offset (SFO) and channel mobility. The ICI degrades orthogonality between different subcarriers in MC-CDMA system due to which Multiple Access Interference (MAI) occurs. The HODO is based on the socio-psychological behavior of humans in the society. Opinion dynamics leads to human consensus and consensus builds up due to human interactions in a society. The proposed approach could be used to introduce human opinion based intelligent communication networks. Our method is novel in the sense that with this algorithm, social sciences could be made compatible with wireless communication technology, which will go a long way to bridge the gap between humans and the communication technology. This new method works with very few number of control parameters and reduces the bit error rate (BER) better as compared with other conventional stochastic methods like Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). Numerical simulation results show that the proposed detector also reduces the computational complexity manifold.

Nonlinear Kalman Filter-Based Robust Channel Estimation for High Mobility OFDM Systems

High-speed train (HST) and vehicle-to-vehicle (V2V), as typical scenes of 5G communication, have attracted extensive attention from academia and industry in recent years. Aiming at the channel characteristics of frequency-selective fading, fast time-varying and time-domain non-stationary in high mobility scenarios, a nonlinear Kalman filter-based high-speed channel estimation algorithm for orthogonal frequency-division multiplexing (OFDM) systems is proposed. We adopt basis expansion model (BEM) to eliminate the inter-subcarrier interference (ICI) caused by the fast time-varying characteristics. For the non-stationary characteristics of high mobility channel, a channel interpolation algorithm based on extended Kalman filter (EKF) is introduced to jointly estimate the channel impulse response (CIR) and time correlation coefficients. However, the EKF channel estimation uses structure of decision feedback to construct the observation matrix, which would lead to error propagation. This paper analyzes the generation of error propagation through theoretical derivation. Furthermore, for the error propagation of EKF, we introduce unscented Kalman filter (UKF) algorithm to perform Gaussian approximation of non-Gaussian observing system, and eliminate the influence by Kalman filter (KF). Simulation results demonstrate that the channel estimation accuracy of BEM-UKF is further improved compared with BEM-EKF, and the influence of pilot distance (PD) is smaller, which further improves the robustness of the algorithm.

Soft-Output Detection Methods for Sparse Millimeter-Wave MIMO Systems With Low-Precision ADCs

The use of low-precision analog-to-digital converters (ADCs) is a low-cost and power-efficient solution for a millimeter wave (mmWave) multiple-input multiple-output (MIMO) system operating at sampling rates higher than a few Gsample/sec. This solution, however, can make significant frame-error-rates (FERs) degradation due to inter-subcarrier interference when applying conventional frequency-domain equalization techniques. In this paper, we propose computationally-efficient yet near-optimal soft-output detection methods for the coded mmWave MIMO systems with low-precision ADCs. The underlying idea of the proposed methods is to construct an extremely sparse inter-symbol-interference (ISI) channel model by jointly exploiting the delay-domain sparsity in mmWave channels and a high quantization noise caused by low-precision ADCs. Then we harness this sparse channel model to create a trellis diagram with a reduced number of states or a factor graph with very sparse edge connections. Using the reduced trellis diagram, we present a soft-output detection method that computes the log-likelihood ratios (LLRs) of coded bits by optimally combining the quantized received signals obtained from multiple receive antennas using a forward-and-backward algorithm. To reduce the computational complexity further, we also present a low-complexity detection method using the sparse factor graph to compute the LLRs in an iterative fashion based on a belief propagation algorithm. Simulations results demonstrate that the proposed soft-output detection methods provide significant FER gains compared to the existing frequency-domain equalization techniques in a coded mmWave MIMO system using one- or two-bit ADCs.

Laser phase noise effect and reduction in self-homodyne optical OFDM transmission system.

We present a laser phase noise (PN) induced effect of a phase-modulation-to-intensity-modulation conversion noise and noise pedestals underneath each of the orthogonal frequency division multiplexing (OFDM) subcarriers in a self-coherent optical OFDM transmission using a self-homodyne technique. We provide a statistical analysis on the received symbols using a histogram to demonstrate the effect of a phase rotation term and inter-subcarrier interference individually and collectively. The PN is then compensated using a simple time delay to realign the phase walk-off of the subcarriers relative to the carrier. Significant quadrature improvements of 6.82 dB using 5 MHz laser linewidth over a 720 km transmission length and 5.38 dB using 20 MHz over 240 km have been obtained with 16 quadrature amplitude modulation (QAM) over 15 GHz OFDM signal bandwidth. The technique also significantly reduced an optical-signal-to-noise ratio requirement at the bit error rate of 1×10-3 by 16.15 dB for 64-QAM over 160 km. With the delay, the system can tolerate three times the chromatic dispersion-length product.

MMSE-based-filter and artificial noise design for MIMO–OFDM systems

Physical layer security is a crucial issue in wireless networks to prevent legitimate communication from eavesdropping. This paper investigates the physical layer security of a wireless multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) communication system in the presence of a multiple-antenna eavesdropper. We first propose a minimum mean square error (MMSE)-based-filter secure MIMO–OFDM system which can destroy the orthogonality of eavesdropper’s signals. The MMSE-based-filter is used at the receiver to suppress the inter-subcarrier interference and disturb the reception of eavesdropper while maintaining the quality of legitimate transmission. Next, we propose another artificial noise (AN)-assisted secure MIMO–OFDM system to further improve the security of the legitimate transmission. The time-domain AN signal is designed to be canceled out at the legitimate receiver. Therefore, AN will disturb the reception of eavesdropper while the legitimate transmission will not be affected. Finally, power allocation for AN signals and subcarriers will be discussed since AN is generated utilizing the residual power of the MIMO–OFDM system. Simulation results are presented to demonstrate the security performance of the proposed transmit filter design and AN-assisted scheme in the MIMO–OFDM system.

Simple Feedforward Carrier Phase Estimation for Optical FBMC/OQAM Systems

Filter-bank multi-carrier based on offset quadrature amplitude modulation (OQAM) has recently been proposed to improve the spectral efficiency of optical fiber communication systems. Unfortunately, it is prone to the laser phase noise (PN) that results in significant inter-subcarrier interference due to the loss of OQAM orthogonality. Based on the analysis of the OQAM constellation obtained at the output of the analysis filter bank, we propose a modified blind phase search algorithm working based on the observation of all subcarriers simultaneously. It efficiently compensates for the PN and incurs a low number of multiplications. The proposed method is analytically derived and numerically validated with 4-, 16-, and 64-OQAM modulations. The impact of the number of subcarriers used per optical channel is also investigated. The results show that up to 256 subcarriers can be utilized with negligible performance degradation. Moreover, the method provides a tolerated linewidth and symbol duration product of $1.4\times 10^{\mathrm {-4}}$ , $2.5\times 10^{\mathrm {\mathbf {-5}}}$ , and $6.2\times 10^{\mathrm {-6}}$ for respective 4-, 16-, and 64-OQAM modulations to limit the SNR penalty to 1 dB at a BER of $10^{\mathrm {-3}}$ .

Comparative Study of Bit Error Rate with Channel Estimation in OFDM System for M-ary Different Modulation Techniques

In this paper we investigate the bit error rate performance of orthogonal frequency division multiplexing system with channel estimation through least square error (LSE) and minimum mean square error (MMSE) algorithms. In this paper we are implementing the M-ary phase shift keying (M- PSK) and M-ary quadrature amplitude modulation (M-QAM) digital modulation techniques for mapping the signal in OFDM system for bit error rate evaluation with the employment of comb-type pilot symbol-assisted channel estimation algorithm over frequency selective multi-path Rayleigh fading channel. Here the performance of Least Squares method depends on not only on the signal-to-noise ratio (SNR) but also on the pilot ratio. Simulation results show that applying the LSE and MMSE channel estimation algorithm, they produce the best BER performance over the fading channel. We can consider the OFDM system as either a modulation technique or a multiplexing technique. In a single carrier system, a single fade or interferer can cause the entire link to fail, but in a multicarrier system, only a small percentage of the subcarriers will be affected [1]. Here we are using the pilot symbols as a guard band to eliminate the Inter Symbol Interference, and cyclic prefix eliminates the Inter Subcarrier Interference. Keywords Channel estimation, orthogonal frequency division multiplexing (OFDM), least square error (LSE), minimum mean square error (MMSE), pilot symbol, bit error rate (BER).

A New Multipath Signals Receiving Scheme Based on DOA Estimation and Beamforming with Multi-antenna

In the vehicle wireless OFDM communication system, the efiect of multipath fading and Doppler frequency shift in channel may cause frequency selective fading at the frequency domain and intersubcarrier interference in an OFDM symbol, which can reduce the system transmission performance. To solve the above problems, this paper proposes a new receiving scheme to eliminate the multipath efiect at OFDM receiver which is to separate multipath signals and extract the main path based on DOA estimation and beamforming (OMSDB). This scheme takes advantage of spatial information of multipath signals, separates path signals and extracts the main path through beamforming each path signal. OMSDB can efiectively extract the main paththus greatly improves the performance of the receiver. In vehicle multipath channel, simulation results verify the efiectiveness of our proposed scheme.

A cost-effective ROF system employing FBG and DML to generate optical mm-wave

We have investigated and experimentally demonstrated a ROF system employing FBG and low-cost DML to generate optical mm-wave. We employ FBG because the bandwidth of the optical modulator is largely reduced and the architecture of the ROF system is simpler. Because no expensive broadband external modulator is used, the overall system is considered as a cost-effective solution. This novel scheme employs low-cost DML to generate mm-wave signal which is a practical scheme to be applied for future broadband access networks. Full Text: PDF References L. Xu and T. Wang, "Key technologies for high-speed digital coherent optical communications", Proc. ICO, pp. 1?2, May, (2011). CrossRef S. Mikel and L. Alayn, "Orthogonally polarized optical single sideband modulation for microwave photonics processing using stimulated Brillouin scattering", Opt. Express, vol. 18, no. 22, pp. 22906?22914, (2010). CrossRef Z. Cao, J. Yu, M. Xia, Q. Tang, Y. Gao, W. Wang, and L. Chen, "Reduction of Intersubcarrier Interference and Frequency-Selective Fading in OFDM-ROF Systems", J. Lightw. Technol., vol. 28, no. 16, 2423?2429, Aug. 15, (2010). CrossRef J. Yu, et al., "Cost-Effective Optical Millimeter Technologies and Field Demonstrations for Very High Throughput Wireless-Over-Fiber Access Systems", J. Lightw. Technol., vol. 28, no. 16, pp. 2376?2397, Aug. 15, (2010). CrossRef C. Tsekrekos, T. Kuri, and K. Kitayama, "Distribution of Millimeter-Wave and Baseband Services Over an Integrated Reconfigurable Access Network Platform", J. Lightw. Technol., vol. 28, no. 19, pp. 2783?2790, Oct. 1, (2010). CrossRef Z. Dong, J. Lu, Y. Pi, X. Lei, L. Chen, and J. Yu, "Optical millimeter-wave signal generation and wavelength reuse for upstream connection in radio-over-fiber systems", Journal of Optical Networking, 7, 736-741, (2008). CrossRef W. Jiang, C. T. Lin, A. Ng'oma, P. T. Shih, J. Chen, M. Sauer, F. Annunziata and S. Chi, "Simple 14-Gb/s Short-Range Radio-Over-Fiber System Employing a Single-Electrode MZM for 60-GHz Wireless Applications", J Lightw Technol., vol.28, no. 16, 2238-2246, (2010). CrossRef J. Ma, "5 Gbit/s Full-Duplex Radio-Over-Fiber Link With Optical Millimeter-Wave Generation by Quadrupling the Frequency of the Electrical RF Carrier", J. Opt. Commun. Netw., vol.3, no. 2, 127-133, (2011). CrossRef Z. Cao, J. Yu, H. Zhou, W. Wang, M. Xia, J. Wang, Q. Tang and L. Chen, "WDM-RoF-PON Architecture for Flexible Wireless and Wire-Line Layout", J. Opt. Commun. Netw., vol. 2, no. 2, 117-121, (2010). CrossRef J. Yu, J. Gu, X. Liu, Z. Jia, G. Chang, "Seamless integration of an 8×2.5 Gb/s WDM-PON and radio-over-fiber using all-optical up-conversion based on Raman-assisted FWM", IEEE Photon. Technol. Lett. 17, 1986-1988, (2005). CrossRef J. Seo, Y. Seo, W. Choi, "1.244-gb/s data distribution in 60-GHz remote optical frequency up-conversion systems", IEEE Photon. Technol. Lett. 18, 1389-1391, (2006). CrossRef J. Yu, Z. Jia, G. Chang, "All-optical mixer based on cross-absorption modulation in electroabsorption modulator", IEEE Photon. Technol. Lett. 18, 2421-2423, (2005). CrossRef H. Song, J. Lee, "Error-free simultaneous all-optical upconversion of WDM radio-over-fiber signals ", IEEE Photon. Technol. Lett. 17, 1731-1733, (2005). CrossRef J. Yu, Z. Jia, L. Yi, Y. Su, G. Chang, "Optical millimeter-wave generation or up-conversion using external modulators", IEEE Photon. Technol. Lett. 18, 265-267, (2006). CrossRef Jianjun Yu, Z. Jia, L. Xu, L.Chen, T. Wang, and G. K, Chang, "DWDM optical millimeter-wave generation for radio-over-fiber using an optical phase modulator and an optical interleaver", IEEE Photon. Technol. Lett. 18, 1418- 1420, (2006). CrossRef M. Attygalle, C. Lim, G. Pendock, A. Nirmalathas and G. Edvell, "Transmission improvement in fiber wireless links using fiber Bragg gratings", IEEE Photon. Technol. Lett. 17, 190- 192, (2005). CrossRef L. Chen, J. He, Y. Li, H. Wen, Y. Shao, C. Huang, L. Hu, Y. Pi, Z. Dong, Y. Li, X. Lei and S. Wen, "Simple ROF configuration to simultaneously realize optical millimeter-wave signal generation and source-free base station operation", ECOC, vol.2, 45-46, (2007) . DirectLink

Analysis of effect of high-power amplifier modelling on the performance of orthogonal frequency division multiplexing transceiver for wireless communications

This study presents an exact theoretical analysis of performance degradation in OFDM system when the signal including phase noise is passed through a dynamic non-linear circuit such as HPA. The HPA is modelled using a memory polynomial model. The theoretical analysis shows that the detected data symbol at the receiver include common phase error, intersubcarrier interference and intermodulation components. The analytical expressions for intermodulation term are derived using combinatorial methods. Using the derived expressions, a closed form SNR at the output, degradation factor and hence, the probability of error can be evaluated theoretically. The results show that when the OFDM signal with phase noise passes through dynamic non-linear circuit, the phase noise expansion occurs. This expansion is related to the memory length of non-linear device and causes higher degradation in OFDM signal. By use of this exact analysis, designers can choose optimum parameters and operating point of HPA for a desired performance of OFDM transceiver. This reduces energy consumption. To verify the accuracy of the analysis, a comparison between the theoretical and simulated results is presented. The comparison shows that the BER of analytical results closely matches with the simulation results of the OFDM system.

Impairment Mitigation for a 60 GHz OFDM Radio-Over-Fiber System Through an Adaptive Modulation Technique

We investigate several existing impairments in an orthogonal frequency-division-multiplexed radio-over-fiber (OFDM-ROF) system delivering a 60 GHz optical millimeter wave with double optical sidebands and a suppressed central carrier. It is found through theoretical analysis and numerical simulation that intersubcarrier interference and frequency-selective fading are the dominant factors degrading the OFDM-ROF system performance. With that in mind, we propose and experimentally demonstrate what we believe to be a novel scheme to mitigate system impairments in an OFDM-ROF link by using the adaptive modulation technique in which different subcarriers may have different modulation formats according to their signal-to-noise ratio over the ROF channel.

Reduction of Intersubcarrier Interference and Frequency-Selective Fading in OFDM-ROF Systems

This paper theoretically investigates the signal degradation induced by intersubcarrier interference and frequency-selective fading in orthogonal frequency-division-multiplexing radio-over-fiber systems. Turbo codes and bit interleaver technologies are proposed to effectively mitigate unbalanced error distribution because of intersubcarrier interference and frequency-selective fading. Experimental results show that the receiver sensitivities are improved as far as 5 dB after 50-km SMF-28 transmission for 6.25-Gb/s wireless signals on optical generated 60-GHz carrier.

Analytical performance evaluation of the OFDM systems in the presence of jointly fifth order nonlinearity and phase noise

This paper presents an exact theoretical analysis of the performance degradation in an orthogonal frequency division multiplexing (OFDM) system when the signal including phase noise is passed through a nonlinear circuit such as high power amplifier (HPA). This circuit is modeled as a fifth order memory-less nonlinear polynomial model (5th order MLNPM). The nonlinear model is derived from important electrical parameters such as gain, 1-dB compression and 3rd order intercept point. Theoretical analysis shows that the detected data symbol at the receiver consists of attenuated version of the original transmitted data symbol, common phase error (CPE), inter-sub-carrier interference (ICI), third and fifth order intermodulation (IM) components. The analytical expressions for intermodulation noise term are derived using combinatorial methods. By use of the derived expressions, a closed-form output signal to noise ratio (SNR), degradation factor (DF) and probability of error can be evaluated theoretically. For verifying the accuracy of our analysis, comparisons between the theoretical and simulated results with electrical parameter of an actual and applicable HPA are presented. The comparisons show that bit error rate (BER) of analytical results is closely match with simulation results for OFDM system using M-QAM modulation.

Inter-subcarrier interference compensation in the frequency-hopped single-carrier frequency division multiple access communication system

Single-carrier frequency division multiple access (SC-FDMA) system having very good characteristic on peak-to-average power ratio is promising in communication area. But the performance of SC-FDMA system is very sensitive to inter-subcarrier interference (ICI), and existing phase noise suppression algorithm has reduced just phase noise only. Therefore the authors propose effective method, phase noise and frequency offset suppression (PNFS) algorithm, using comb-type pilot. PNFS algorithm can suppress phase noise, carrier frequency offset and even Doppler effect simultaneously in frequency domain. Through PNFS algorithm, SC-FDMA system has robust characteristic against ICI of performance degradation. Moreover, in these days, most electronic communication systems are weak to jamming. So, frequency-hopped (FH) scheme, which is one kind of spread spectrum techniques as a means of making performance better to supplement a disadvantage of SC-FDMA system on jamming attack, is considered. The authors would like to analyse ICI and jamming in SC-FDMA system and employ FH technique in SC-FDMA system because existing studies have not considered the situation regarding ICI and jamming exist simultaneously in mobile channel. So, the authors analyse degradation factors in FH-SC-FDMA system about ICI and jamming signal categorised as partial band jamming and multi-tone jamming. Then, the proposed FH-SC-FDMA system using PNFS algorithm has strong performances about ICI and jamming.

Joint data QR-detection and Kalman estimation for OFDM time-varying Rayleigh channel complex gains

This paper deals with the case of a high speed mobile receiver operating in an orthogonal-frequency-division-multiplexing (OFDM) communication system. Assuming the knowledge of delay-related information, we propose an iterative algorithm for joint multi-path Rayleigh channel complex gains estimation and data recovery in fast fading environments. Each complex gain time-variation, within one OFDM symbol, is approximated by a polynomial representation. Based on the Jakes process, an auto-regressive (AR) model of the polynomial coefficients dynamics is built, making it possible to employ the Kalman filter estimator for the polynomial coefficients. Hence, the channel matrix is easily computed, and the data symbol is estimated with free inter-sub-carrier-interference (ICI) thanks to the use of a QR-decomposition of the channel matrix. Our claims are supported by theoretical analysis and simulation results, which are obtained considering Jakes' channels with high Doppler spreads.

Saturation throughput analysis of WAVE networks in Doppler spread scenarios

IEEE 802.11p, also known as wireless access in vehicular environment (WAVE), extends the applications of IEEE 802.11 to a fast fading vehicular communication environment. In WAVE systems, Doppler effect should not be ignored because of the high velocity of vehicles. Hence, in this paper the authors study the characteristics of physical layer WAVE system in the presence of the Doppler spectrum, such as symbol error rate performance and inter-subcarrier interference power. The throughput performance expression of a WAVE system is derived theoretically, which is the function of the frame size, number of the nodes, transmission probability, frame error rate and Doppler spread. Based on the obtained expressions, the optimal frame size, transmission probability and the number of nodes supportable in the WAVE system are derived to evaluate the maximum throughput performance. Finally, to validate the analytical results, simulations have been conducted to show the effectiveness of the proposed scheme.

Analysis of CFO effects on and phase compensation method for SC-FDMA systems

Discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) based single carrier-frequency division multiple access (SC-FDMA) is accepted as the uplink transmission scheme by the 3GPP-long term evolution standardization organization. In this paper, the effects of carrier frequency offset (CFO) on DFT-S-OFDM system are analyzed for both single user and multiple user accessing scenarios. According to the analysis, the CFO results in the attenuation, linear phase rotation, inter-symbol interference (ISI) and inter-sub-carrier interference (ICI) on the demodulated symbols of each desired user, and the multi-user interference (MUI) among uplink users. The theoretical values of ISI, ICI, and signal to interference ratio (SIR) are presented for the DFT-S-OFDM system with full and partial bandwidth detection respectively. A phase compensation method is proposed to reduce the effect of linear phase rotation on the demodulated symbols. Finally, the analytical values are verified by the simulation results.