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The speed of the target can be estimated by the sound pressure cross-correlation of the line spectrum of the moving target at different time intervals. However, a slight deviation of the line spectrum has a significant influence on the estimated result. In this paper this phenomenon is analyzed from the theory, then the speed of the target is estimated when the line spectrum is biased. Experimental...
The aim of this contribution is to discuss an environmental filtering technique in array diagnosis. The basic idea is to distinguish the array contribution from the interference field using sparsity as discriminant by means of differential measurement technique. Basically, the field associated to the fault elements is separated by the field radiated by interference source using a mixed minimum ℓ1...
Timer interference arises when a high-priority realtime task is delayed by a timer interrupt that is intended for a lower-priority task. We demonstrate that high-resolution timers, as exposed for instance by Linux's hrtimer API, can cause substantial timer interference, which manifests as significantly increased response times and lowered throughput. To eliminate this source of unpredictability, we...
In this paper, a new algorithm to suppress the interferences for Direction-of-Arrival(DOA) estimation is presented. The method is based on the property of the noise subspace invariant to power of emitters. With theoretical analysis and computer simulations, it is shown that the proposed method has a good performance on signal DOA estimation under disturbances.
The performance of adaptive beamformer will degrade in the case of jammer motion and shaking platform. In order to improve the performance of adaptive beamformer, an improved null broadening adaptive beamforming method is proposed. The proposed method is realized by the reconstruction of interference-plus-noise covariance matrix. Null broadening can be obtained by the proposed method and the null...
Random stepped FM radar that transmits random frequency narrowband pulses can avoid interference between adjacent radar systems. The random stepped FM radar also offers spectrum hole since it consists of independent pulses with different frequency. Thus it is expected to coexist with the existing radar systems. In this paper, we propose to adopt Khatri-Rao product array processing to spectrum hole...
To do the radiation emission measurement in RF integrated system, near-field measurement method was adopted. As near-field data is a relative value, far-field data was needed and the study of the conversion problem from near-field to far-field was required. In this paper a method, based on an array of dipoles, was proposed to model equivalent interference sources through using regularization technique.
The usage of antenna arrays brought innumerable benefits to radio systems in the last decades. Arrays can have multidimensional structures that can be exploited to achieve superior performance and lower complexity. However, the literature has not explored yet all the advantages arising from these features. This paper uses tensors to provide a method to design efficient beamformers for multidimensional...
A 60GHz-band compact-range wireless access system using a large array antenna can provide an uniform signal reception zone (less than 14 m distance from the antenna) and an almost multipath-free propagation environment. To evaluate the system performance, a wireless communication system for demonstration is constructed and the bit error rate (BER) and the signal-to-interference-plus-noise ratio (SINR)...
In this paper, we propose a novel algorithm for underdetermined blind identification problem in blind source separation. The proposed algorithm is based on the charrelation matrix of observed signals. The charrelation matrix not only can be considered as a generalized second-order covariance matrix, but also incorporates higher-order information. It is significant for blind separation problem based...
It is shown that implementation of the method of space-time division multiple access with the individual space-time processing of subscriber stations signals which is reduced to the use of group elements of adaptive antenna array and the establishment of parallel procedures of assessing values of vector of weighting coefficients on the number of simultaneously working stations.
The exponential increase of global mobile data traffic requires future 5G system. Millimeter Waveform (mmWave) band is being considered as a candidate for new radio bands for 5G systems. In this paper, we present beam-forming technology on patch antenna array to cope path loss of mmWave band. In order to reduce the interference between beams and to compensate for this problems of limitation of user...
Millimeter wave (mmW) communication has emerged as a promising component of the access link for 5G cellular systems. In order to overcome the higher free-space path loss at these frequencies, high gain, and therefore highly directional, antennas are being proposed at both ends of the link. Furthermore, in order to maintain a mobile connection with an acceptable quality of service (QOS), these highly...
In multiple source detection of using an array, the threshold of the generalized likelihood ratio test (GLRT) is only related with the noise power. And the false alarm probability will increase when one signal is present in the sidelobe of beamformer's pattern because of energy leakage. A constant false alarm ratio (CFAR) based multiple-source detection algorithm was proposed in this paper. The detection...
In this paper, we investigate a preference-aware multicast mechanism in active array aided LTE (Long Term Evolution) networks. An active antenna system can direct vertical beams in different horizontal and vertical directions, so the amount of energy delivered is more concentrated on the target users. Employing the active array, each multicast group is provided with an individual beam with specific...
In order to avoid eavesdropping, beamforming can be used not only to induce artificial noise or jamming signal to an eavesdropper, but also transmit desired signals to a legitimate user (or sensor) from an access point (AP) equipped with an antenna array. In this paper, with proper power allocation, we show that beamforming under a rich scattering environment can guarantee a certain secrecy rate with...
Several terrestrial communication systems use the same frequency spectrum as Global Navigation Satellite Systems (GNSS) or bands close to it. Pseudolites constitute one such system that generally uses the GNSS spectrum for signal propagation. The signals from pseudolites in the operating region play a crucial role in augmenting satellite based user navigation. These signal transmitters are deployed...
With the emergence of large high-rise buildings and three-dimensional (3D) space distribution of wireless traffics, there exists a new demand of forming seamless high-quality coverage of the common control signals in cellular mobile communication networks. In this paper, 3D coverage control mechanism based on beamforming using planer array antenna of base station (BS) is explored. A novel multi-sector...
The proposed method realizes adaptive reduced-dimension processing based on joint optimization of both reduced-dimension matrix and beam-forming weight vector. Meanwhile, the spatial spectrum reconstruction technology is used to update the covariance matrix of array data online. The simulation results show that the proposed method is robust to the dimension of the reduced-dimension matrix and significantly...
The convergence rate of the power inversion (PI) algorithm utilized in null steering antenna is of vital importance to handle interferences in efficient way. This paper presents the in-depth analysis of the factors affecting the convergence rate of null steering antenna utilizing power inversion algorithm. Apart from choosing optimum value of step size, factors like number of snapshots, signal structure,...
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