In this paper, a beampattern design method is proposed for the multi-input-multi-output (MIMO) dual-function radar-communication (DFRC) system with an interleaved array. To make full use of the whole aperture, first, ...
详细信息
ISBN:
(纸本)9781728119465
In this paper, a beampattern design method is proposed for the multi-input-multi-output (MIMO) dual-function radar-communication (DFRC) system with an interleaved array. To make full use of the whole aperture, first, the transmit array is partitioned into two interleaved subarrays, one is for radar and the other is for downlink communications. Then, both the radar waveform and communication beamformers are optimized by combining the null-space projection (NSP) method and cyclic approach (CA) to perform the coexistence of MIMO radar and downlink communications. Besides, the communication beampattern can be utilized to improve the detection performance. Finally, several numerical results are given to show the effectiveness of the proposed method.
Nonuniform linear arrays (NLAs) have attracted considerable attention owing to their capability to enhance the degrees of freedom (DOF) and increase the array aperture, which is essential for improving performance in ...
详细信息
Nonuniform linear arrays (NLAs) have attracted considerable attention owing to their capability to enhance the degrees of freedom (DOF) and increase the array aperture, which is essential for improving performance in terms of both the direction of arrival estimation and adaptive beamforming. This paper presents two new NLAs, namely interleaved coprime array (ICA) and augmented interleaved array (AIA). The ICA consists of two uniform linear subarrays, whose inter-element spacings are coprime integers. The ICA can obtain more uniform degrees of freedom (uDOF), while maintaining weak mutual coupling effects, because its configuration includes only minority sensors interleaved. The optimal configuration of the ICA is deduced using the principle of maximizing the uDOF. Moreover, the AIA geometry is obtained by removing a redundant element in the ICA and appropriately designing the location of the additional element. For a fixed total number of sensors, the AIA can gain more uDOF and DOF than the ICA, while exhibiting lower mutual coupling effects. The closed-form expressions for the properties of the proposed array structures involving an arbitrary number of sensors are also derived. Numerical simulations are performed to verify the superiority of the proposed arrays over other sparse arrays.
Most global optimization based synthesis procedures act in essentially the same way on all the involved variables. In this paper, it is theoretically discussed and numerically emphasized how explicit exploitation of t...
详细信息
Most global optimization based synthesis procedures act in essentially the same way on all the involved variables. In this paper, it is theoretically discussed and numerically emphasized how explicit exploitation of the convexity of the problem with respect to a part of the degrees of freedom (when available) allows to achieve increased performances with, respect to previous results, and to develop new interesting design solutions. Examples are presented for the synthesis of both sum and difference patterns by using nonuniformly spaced arrays and for the so called "optimal compromise amongst sum and difference patterns." Finally, the proposed approach is exploited in developing effective design solutions (based on the concept of interleaved arrays) to the problem of achieving very flexible antennas while using simple feeding networks. As an example, array antennas capable to radiate two different beams with individually steerable patterns, or to perform jammer rejection at the physical layer or even to realize a "flat-top" beam pattern are synthesized and presented.
A conventional monopulse radar system uses three beams, namely, sum beam, elevation difference beam, and azimuth difference beam, which require different layers of weights to synthesize each beam independently. Since ...
详细信息
A conventional monopulse radar system uses three beams, namely, sum beam, elevation difference beam, and azimuth difference beam, which require different layers of weights to synthesize each beam independently. Since the multilayer structure increases the hardware complexity, many simplified structures based on a single layer of weights have been suggested. In this communication, we introduce a new technique for finding disjoint and fully covering sets of weight vectors, each of which constitutes a sparse subarray, forming a single beam. Our algorithm decomposes the original nonconvex optimization problem for finding disjoint weight vectors into a sequence of convex problems. We demonstrate the convergence of the algorithm and show that the interleaved array structure is able to meet difficult beam constraints.
Antenna radiation pattern measurement has been a challenge to many researchers, especially when the size of the antenna is large due to the requirement of a large anechoic chamber. Furthermore, a quick measurement pro...
详细信息
ISBN:
(纸本)9781728123967
Antenna radiation pattern measurement has been a challenge to many researchers, especially when the size of the antenna is large due to the requirement of a large anechoic chamber. Furthermore, a quick measurement process is required when many radiation patterns need to be measured. In this paper, a measuring system to measure a large interleaved linear array antenna of a total length of 1.35 meters operating at C band frequency was constructed. The measuring system was constructed with an azimuth range capable of nearly 180 and able to measure radiation patterns of an array with linear or circular polarization. Typical measurement speed to provide a sample of 1028 measurements points is 16 seconds, with 0.116 resolution for 120 azimuth range without a positioner component.
暂无评论