This paper investigates the device-to-device(D2 D) communication underlaying multi-user multi-input multi-output(MU-MIMO) cellular networks. It is assumed that D2 D users reuse the downlink time-frequency resources of...This paper investigates the device-to-device(D2 D) communication underlaying multi-user multi-input multi-output(MU-MIMO) cellular networks. It is assumed that D2 D users reuse the downlink time-frequency resources of cellular links, and the base station(BS) is assumed to be equipped with multiple antennas. We investigate the ergodic achievable sum rate of the system when the interference cancellation(IC) precoding strategy is employed at the BS. The distributions of the received signal-to-interference-plus-noise ratio(SINR) for each link are firstly analyzed, and an exact ergodic achievable sum rate of the whole system with closedform expressions is then derived. Furthermore, we present novel upper and lower bounds with simpler expressions, which are later verified to be fairly close to the Monte-Carlo simulations. All the expressions we presented are suitable for arbitrary network topology and arbitrary number of antennas at BS. Based on the derived bounds, the influence of the antennas at BS on system performance is then analyzed. We reveal that the system performance increases along with the number of antennas at BS in a logarithmic way. The accuracy of our analytical results is validated via comparisons with Monte-Carlo simulations.展开更多
The aeronautical en-route communication channel is modeled as a two-ray double-selective channel. Based on the channel model, a low-eomplexity iteration self-cancellation algorithm is proposed to cancel the inter-carr...The aeronautical en-route communication channel is modeled as a two-ray double-selective channel. Based on the channel model, a low-eomplexity iteration self-cancellation algorithm is proposed to cancel the inter-carrier interference （ICI） of orthogonal frequency division multiplexing （OFDM） system in aeronautical communications. ICI can be completely suppressed by the proposed algorithm if channel parameters are estimated ideally. We analyzed the SNR loss with variant iteration times theoretically, and pointed out how to choose the optimum iteration times. The algorithm is especially useful to the situation with high aviation veloc- ity, as less iteration is sufficient to separate the interference with larger Doppler shift, and less noise will he introduced. We carried out Monte Carlo simulation with typical aeronautical en-route channel, and the simulation results are in agreement with the deduced theoretical performance expressions and validate the effect of our cancellation algorithm.展开更多
Interference is a key factor in radar return misdetection.Strong interference might make it difficult to detect the signal or targets.When interference occurs in the sidelobes of the antenna pattern,Sidelobe Cancellat...Interference is a key factor in radar return misdetection.Strong interference might make it difficult to detect the signal or targets.When interference occurs in the sidelobes of the antenna pattern,Sidelobe Cancellation(SLC)and Sidelobe Blanking are two unique solutions to solve this problem(SLB).Aside from this approach,the probability of false alert and likelihood of detection are the most essential parameters in radar.The chance of a false alarm for any radar system should be minimal,and as a result,the probability of detection should be high.There are several interference cancellation strategies in the literature that are used to sustain consistent false alarms regardless of the clutter environment.With the necessity for interference cancellation methods and the constant false alarm rate(CFAR),the Maisel SLC algorithm has been modified to create a new algorithm for recognizing targets in the presence of severe interference.The received radar returns and interference are simulated as non-stationary in this approach,and side-lobe interference is cancelled using an adaptive algorithm.By comparing the performance of adaptive algorithms,simulation results are shown.In a severe clutter situation,the simulation results demonstrate a considerable increase in target recognition and signal to noise ratio when compared to the previous technique.展开更多
基金supported by the Natural Science Foundation of Jiangsu Province (No. BK20170758)the National Natural Science Foundation for Young Scholars of China (No. 61701201)+1 种基金the Natural Science Foundation for colleges and universities of Jiangsu Province (No. 17KJB510011)Project of Key Laboratory of Wireless Communications of Jiangsu Province
文摘This paper investigates the device-to-device(D2 D) communication underlaying multi-user multi-input multi-output(MU-MIMO) cellular networks. It is assumed that D2 D users reuse the downlink time-frequency resources of cellular links, and the base station(BS) is assumed to be equipped with multiple antennas. We investigate the ergodic achievable sum rate of the system when the interference cancellation(IC) precoding strategy is employed at the BS. The distributions of the received signal-to-interference-plus-noise ratio(SINR) for each link are firstly analyzed, and an exact ergodic achievable sum rate of the whole system with closedform expressions is then derived. Furthermore, we present novel upper and lower bounds with simpler expressions, which are later verified to be fairly close to the Monte-Carlo simulations. All the expressions we presented are suitable for arbitrary network topology and arbitrary number of antennas at BS. Based on the derived bounds, the influence of the antennas at BS on system performance is then analyzed. We reveal that the system performance increases along with the number of antennas at BS in a logarithmic way. The accuracy of our analytical results is validated via comparisons with Monte-Carlo simulations.
基金Sponsored by the National"863" Program Project(2007AA01Z293)
文摘The aeronautical en-route communication channel is modeled as a two-ray double-selective channel. Based on the channel model, a low-eomplexity iteration self-cancellation algorithm is proposed to cancel the inter-carrier interference （ICI） of orthogonal frequency division multiplexing （OFDM） system in aeronautical communications. ICI can be completely suppressed by the proposed algorithm if channel parameters are estimated ideally. We analyzed the SNR loss with variant iteration times theoretically, and pointed out how to choose the optimum iteration times. The algorithm is especially useful to the situation with high aviation veloc- ity, as less iteration is sufficient to separate the interference with larger Doppler shift, and less noise will he introduced. We carried out Monte Carlo simulation with typical aeronautical en-route channel, and the simulation results are in agreement with the deduced theoretical performance expressions and validate the effect of our cancellation algorithm.
文摘Interference is a key factor in radar return misdetection.Strong interference might make it difficult to detect the signal or targets.When interference occurs in the sidelobes of the antenna pattern,Sidelobe Cancellation(SLC)and Sidelobe Blanking are two unique solutions to solve this problem(SLB).Aside from this approach,the probability of false alert and likelihood of detection are the most essential parameters in radar.The chance of a false alarm for any radar system should be minimal,and as a result,the probability of detection should be high.There are several interference cancellation strategies in the literature that are used to sustain consistent false alarms regardless of the clutter environment.With the necessity for interference cancellation methods and the constant false alarm rate(CFAR),the Maisel SLC algorithm has been modified to create a new algorithm for recognizing targets in the presence of severe interference.The received radar returns and interference are simulated as non-stationary in this approach,and side-lobe interference is cancelled using an adaptive algorithm.By comparing the performance of adaptive algorithms,simulation results are shown.In a severe clutter situation,the simulation results demonstrate a considerable increase in target recognition and signal to noise ratio when compared to the previous technique.
