Linear and Planar Array Pattern Nulling via Compressed Sensing

Antenna array pattern synthesis technology plays a vital role in the field of smart antennas. It is well known that the pattern synthesis of homogeneous array is the key topic of pattern synthesis technology. But this technology needs plenty of homogeneous array elements to meet the antenna requirements. So, a novel pattern synthesis technology for sparse array based on the compressed sensing (CS) and low-rank matrix recovery (LRMR) methods is proposed. The proposed technology predominantly includes the design of sparse array, the recovery of homogeneous array, and the synthesis of antenna array pattern. The simulation result shows that an antenna array with low gain and strong directivity can be arbitrarily built by the use of a small amount of sparse array elements and it is useful for the miniaturization and economical efficiency of the antenna system.

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Radiation Pattern Synthesis of Planar Arrays Using Parasitic Patches Fed by a Small Number of Active Elements

Modern Printed-Circuit Antennas ◽

10.5772/intechopen.88836 ◽

2020 ◽

Author(s):

Jafar Ramadhan Mohammed ◽

Karam Mudhafar Younus

Keyword(s):

Computer Simulation ◽

Radiation Pattern ◽

Sidelobe Level ◽

Pattern Synthesis ◽

Active Elements ◽

Array Pattern ◽

Planar Arrays ◽

Planar Array ◽

Simulation Results ◽

The Cost

In this chapter, several planar array designs based on the use of a small number of the active elements located at the center of the planar array surrounded by another number of the uniformly distributed parasitic elements are investigated. The parasitic elements are used to modify the radiation pattern of the central active elements. The overall radiation pattern of the resulting planar array with a small number of active elements is found to be comparable to that of the fully active array elements with a smaller sidelobe level (SLL) at the cost of a relatively wider beamwidth and lower directivity. Nevertheless, the uses of only a small number of the active elements provide a very simple feeding network that reduces the cost and the complexity of the array. Simulation results which have been computed using computer simulation technology-microwave studio (CST-MWS) show that the sidelobe level of the designed array pattern with parasitic elements is considerably better than that of the similar fully active array elements. The proposed array can be effectively and efficiently used in the applications that require wider antenna beams.

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Design of a Broadband Array Pattern of Underwater Cymbal Transducers

Sensors ◽

10.3390/s21186119 ◽

2021 ◽

Vol 21 (18) ◽

pp. 6119

Author(s):

Donghyun Kim ◽

Hayeong Shim ◽

Changmin Oh ◽

Kyungseop Kim ◽

Heeseon Seo ◽

...

Keyword(s):

Energy Conversion Efficiency ◽

Voltage Response ◽

Single Element ◽

Frequency Bandwidth ◽

Fractional Bandwidth ◽

Acoustic Characteristics ◽

Structural Pattern ◽

Array Pattern ◽

Planar Array ◽

The Difference

Cymbal transducers are frequently used as an array rather than a single element because of their high quality factor and low energy conversion efficiency. When used as an array, cymbal transducers are likely to have a big change in their frequency characteristics due to the interaction with neighboring elements. In this study, we designed an array pattern of cymbal transducers to achieve a wide frequency bandwidth using this property. First, cymbal transducers with specific center frequencies were designed. Next, a 2 × 2 planar array was constructed with the designed transducers, where dielectric polarity directions of the transducers were divided into two cases (i.e., same and different). For the array, the effect of the difference in the center frequencies and the spacing between the transducers on the acoustic characteristics of the entire array was analyzed. Based on the results, the structural pattern of the array was optimized to have the maximum fractional bandwidth while maintaining the transmitting voltage response over a given requirement. The design validity was verified by making cymbal array prototypes, followed by measuring their performances and comparing them with that of the design.

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