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In this paper, we demonstrate the performance of low complexity soft interference cancellation minimum mean-squared error (SIC-MMSE) detection method for a turbo coded multiple-input multiple-output (MIMO) system with joint iterative detection and decoding (JIDD) principle. The main computational burden of SIC-MMSE detector lies in the multiple inverse operation of the filtering process and maximum...
This work investigates the impact of imperfect statistical information in the uplink of massive MIMO systems. In particular, we first show why covariance information is needed and then propose two schemes for covariance matrix estimation. A lower bound on the spectral efficiency (SE) of any combining scheme is derived, under imperfect covariance knowledge, and a closed-form expression is computed...
There has been growing interest in millimeter wave (mmWave) multiple-input multiple-output (MIMO) systems, which would likely employ hybrid analog-digital precoding with large-scale analog arrays deployed at wide bandwidths. Primary challenges here are how to efficiently estimate the large-dimensional frequency-selective channels and customize the wideband hybrid analog-digital precoders and combiners...
This paper considers the problem of target localization from the bistatic range-sum measurements in noncoherent distributed multiple-input multiple-output (MIMO) radar system. The localization procedure includes two parts. First, it divides the measurements into several groups based on the different transmitter or receiver, and for each group, we use least squares (LS) approach based on squared range-sum...
Massive MIMO and beamforming is commonly considered as one of the key technologies for future cellular communications. It is targeted to solve the capacity requirements in enhanced mobile broadband and enable new services in other communication fields, e.g. machine type communications. In this work, we study M-MIMO technology in a novel approach, combining system simulations and modeling with hardware...
Spatial channel covariance information can replace full channel state information for designing analog precoders in millimeter wave (mmWave) hybrid MIMO systems. Hybrid MIMO architectures, however, make it challenging to estimate the spatial channel covariance matrix because the estimator in baseband can only see the low-dimensional projections of the original channel. In this paper, we propose two...
Recently, an IEEE802.11n access point (AP) has become common in the wireless local-area network (WLAN) due to the high-speed data transmission using the multiple input multiple output (MIMO) technology. However, the signal propagation from the 802.11n AP may not be uniform in the circumferential direction because of multiple antennas in MIMO, in addition to the height direction. As a result, the data...
Network diversity multiple access or NDMA is the family of algorithms with the highest potential throughput in the literature of signal-processing-assisted random access. NDMA uses the concept of protocol-induced retransmissions to create an adaptive source of physical (PHY) layer diversity. This adaptive diversity is used to resolve packet collisions (via signal separation) without the explicit need...
Network diversity multiple access (NDMA) is the family of algorithms with the highest potential throughput in the literature of signal-processing assisted random access protocols. NDMA uses the concept of protocol-induced retransmissions to create an adaptive source of diversity. This diversity is used to resolve packet collisions employing signal separation tools without the explicit need (or as...
In this paper produced effect investigation of thermal and phase noise of frequency synthesizer complex on error of MIMO channel coefficients estimation. Dependence of channel coefficients estimation errors on time mismatch when channel coefficients testing is analyzed. Employment of technique time-division multiplexing is justified. Calculated to dependencies of error estimation on accepted signal...
In high mobility environment, the carrier frequency offset (CFO) introduced by Doppler shifts can severely degrade the system performance. On the other hand, orthogonal pilot sequence which is utilized in conventional frame structure for CFO and channel estimation induces large pilot resource consumption as the number of users increases, resulting in low achievable throughput. In this paper, we propose...
Over the past decade, wireless sensor networks (WSNs) have gained more research attention for their potential applications in, e.g., healthcare, defence and environmental monitoring. However, limited channel capacity and battery life of sensors are the main design challenges in WSNs. The use of cooperative multiple-input multiple-output (MIMO) technology is one of the most promising techniques that...
The combination of MIMO techniques with OFDM, MIMO-OFDM, is a promising way of achieving high spectral efficiency in wireless communication systems. However, the performance of MIMO-ODFM systems is highly degraded by RF impairments such as phase noise. Similar to the SISO case, phase noise in MIMO-OFDM systems results in a common phase error (CPE) and inter carrier interference (ICI). In this paper...
In this paper, we propose a phase noise cancellation algorithm in MIMO-OFDM systems where each transmit (TX) and receive (RX) antenna is equipped with independent oscillator. Most of previous works have considered phase noise model only in SISO-OFDM or simplified phase noise model in MIMO systems assuming that each TX and RX end shares one local oscillator. Recently, however, the local oscillator...
This paper is concerned with the joint estimation of phase noise and time-varying channel responses in full-duplex multiple-input multiple-output (MEMO) orthogonal frequency division multiplexing (OFDM) systems. The time-variation of phase noise and multipath MIMO channel responses gives rise to the identiflability problem of estimating a large number of unknowns which is much greater than the number...
In this paper, a channel estimation method based on the superimposed pilots with the first-order statistics is proposed for massive MIMO systems. In the proposed method, no time slots are cost on training. Hence, transmission rate of the system is higher than the traditional method. Further, a decoder is designed based on MMSE decoder. Finally, simulations show that the performance of the system with...
In this study, two techniques for compensating in-phase/quadrature-phase imbalance (IQI), which are joint estimation and compensation (JEC) and separated estimation and compensation (SEC), have been investigated in the uplink quantized massive MIMO systems. Taking the impacts of both quantization and IQI into consideration, we have expressed the details of the channel estimation and IQI compensation...
The single-carrier frequency-division multiple access (SC-FDMA) or the discrete Fourier transform (DFT) pre-coded orthogonal frequency-division multiple access (OFDMA) technique has been adopted in the uplink transmission of the long term evolution (LTE) terrestrial communication standard, for its lower peak-to-average power ratio (PAPR) and similar receiver complexity, compared with OFDM. It is,...
Accurate and efficient channel estimation methods have the ability to realize the theoretical gain in multi-input multi-output (Massive MIMO) systems which have a massive number of antennas. However, the pilot contamination in Massive MIMO channel estimation process, rooted from the pilot reuse, is a critical problem that severely degrades the performance of the system. This work aims to address the...
This paper presents a recursive parameter estimation algorithm based on a matchable-observable parameterization of multivariable process models. As a consequence of the properties of the models used, no undesired pole-zero cancellations appear, the number of model parameters is not excessive, linear least-squares estimation methods are applicable, and parameter estimation can be accomplished without...
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