Planar Sub-Millimeter-Wave Array Antenna With Enhanced Gain and Reduced Sidelobes for 5G Broadcast Applications

Abstract

In this paper, a compact, broadband, planar array antenna with omnidirectional radiation in horizontal plane is proposed for the 26 GHz fifth-generation (5G) broadcast applications. The antenna element is composed of two dipoles and a substrate integrated cavity (SIC) as the power splitter. The two dipoles are placed side-by-side at both sides of the SIC and they are compensated with each other to form an omni-directional pattern in horizontal plane. By properly combing the resonant frequencies of the dipoles and the SIC, a wide impedance bandwidth from 24 to 29.5 GHz is achieved. To realize a large array while reducing the complexity, loss and size of the feeding network, a novel dual-port structure combined with radiation and power splitting functions is proposed for the 1 st time. The amplitude and phase on each element of the array can be tuned, and therefore, the grating lobes level can be significantly reduced. Based on the dual-port structure, an 8-element array with an enhanced gain of over 12 dBi is designed and prototyped. The proposed antenna also features low profile, low weight and low cost, which is desirable for 5G commercial applications. Measured results agree well with the simulations, showing that the proposed high-gain array antenna has a broad bandwidth, omni-directional pattern in horizontal plane, and low side-lobes.

Non-Uniformly Powered and Spaced Corporate Feeding Power Divider for High-Gain Beam with Low SLL in Millimeter-Wave Antenna Array

“…It is worth mentioning that most of the antenna arrays for the 28 GHz band used uniform excitation and spacing, and showed SLL near −13 dB. Only a non-uniformly powered array showed a lower SLL of −15 dB [ 13 ]. The proposed microstrip line-based power divider implemented non-uniform inter-element spacing, along with amplitude tapering in the 28 GHz band, for the first time, and demonstrated a superior SLL of −17 dB with the 12-patch antenna array.…”

“…In [ 10 ], an antenna array with 16 patches achieved 19.88 dBi gain, with the maximum beam at the boresight near 28 GHz; however, the array did not utilize methods to reduce SLL, and the value was limited to −13.4 dB. The other dipole, patch and aperture antenna arrays for 5G millimeter-wave applications also showed limited SLL values near −10 dB to −15 dB [ 11 , 12 , 13 , 14 , 15 ].…”

Geometrical Synthesis of Sparse Antenna Arrays Using Compressive Sensing for 5G IoT Applications

“…Therefore, the array synthesis problem addressed by a 5G antenna designer is very hard to solve, since it requires to optimize not only the excitations of the array elements, but also their positions and, possibly, their number. This situation identifies the typical problem addressed in the research field represented by the design of sparse antenna arrays [22]. This latter issue has attracted the interests of the research community since the 1960s [23][24][25][26][27], regaining attention in the more recent years thanks to its applicability to the emerging communication scenarios.…”

“…This situation identifies the typical problem addressed in the research field represented by the design of sparse antenna arrays [22]. This latter issue has attracted the interests of the research community since the 1960s [23][24][25][26][27], regaining attention in the more recent years thanks to its applicability to the emerging communication scenarios. Accordingly, several methods have been proposed in the literature for the synthesis of sparse antenna arrays by considering both stochastic and deterministic approaches [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43].…”

“…Nowadays, antenna arrays are widely used in a large variety of scenarios involving far-and near-field focusing/multifocusing applications for satellite, cellular, vehicular, and sensor networks [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. However, even if the array technology is already widespread, its importance is expected to further increase, since the directionality of the communications will represent a basic enabling functionality of the forthcoming fifth-generation (5G) and Internet of things (IoT) systems [18][19][20][21]. This forecast is motivated, on one hand, by the expected presence of a huge number of active devices (smartphones, sensors, actuators), and, on the other hand, by the adoption of the millimeter-wave (mmWave) bands.…”