Vertical Polarization Antenna Research Articles

Multiband Sub-THz Double Angular Characterization in Indoor Scenario

In this article, we present a multiband channel characterization at sub-THz. Three measurement campaigns were conducted in an indoor environment, for different frequency ranges: 125–155, 235–265, and 270–300 GHz, by exploiting a single (vertical) polarization antenna and performing only the azimuth plane. Line-of-sight (LOS) and nonline-of-sight (NLOS), given by human body obstructions and walls, are considered. From directional measurements, the omnidirectional power angular delay profile was extracted. Modeling of large-scale parameters and cluster study are presented.

A dual‐polarized end‐fire mmWave antenna array without ground clearance for 5G mobile terminals

A broadband dual-polarized end-fire millimeter-wave antenna array without ground clearance is proposed in this paper for 5G communication terminals. Horizontally polarized (HP) and vertically polarized (VP) radiation are realized using a quasi-Yagi antenna and a substrate-integrated waveguide cavity antenna, respectively. A multilayer dielectric plate for which the relative dielectric constant increases from top to bottom is used to achieve the HP antenna's end-fire radiation without ground clearance. The VP antenna is implemented using the HP antenna, GND, and three rows of metallic vias. The HP and VP antennas are located in the same area, making the integrated design very compact. An inverted L-shaped feeding structure was used to broaden the VP antenna's bandwidth with a low profile (0.12λL). Finally, a 4 × 1 array was processed to verify the proposed antenna. The measured results show that the overlapping bandwidth is 24 to 29.5 GHz (20.6%) for two polarization modes. The maximum gain varies between 7.6 to 9.1 and 6.5 to 9.1 dBi for the HP and VP modes, respectively.

Wideband Vertically Polarized Antenna With Endfire Radiation for 5G Mobile Phone Applications

This letter presents a wideband slotted substrate integrated waveguide (SIW) antenna for millimeter-wave (mm-wave) fifth-generation (5G) mobile handset applications. The antenna is vertically polarized and has a small clearance of 3.3 mm. To realize a wide operating bandwidth, two sets of vias are employed to perform a change in SIW height. Furthermore, a pair of U-shaped slots is used in both top and bottom faces of SIW to improve impedance matching and front-to-back radiation ratio. The antenna achieves a measured −6 dB bandwidth of 35.7% (23.4–33.6 GHz) and a −10 dB bandwidth of 17.4% (26.2–31.2 GHz). The beamforming capability of the antenna array is investigated. The antenna array has good scanning performance and achieves large spatial coverage.

An Alternative Experimental Determination of a Two-Port Dipolar Antenna Model

It has been shown previously that a symmetric antenna such as a dipole driven via a balun from a coaxial transmission line can be represented as a 3-terminal, 2-port network and that for vertically-polarized antennas operated near ground this network is asymmetric. An experimental approach for the determination of the values of the elements in this network representation has also previously been given. Although reasonably good agreement between simulation and experiment was obtained, the experimental procedure required three 1-port measurements and could not accommodate full error correction in the vector network analyzer (VNA) calibration. Therefore, we consider an alternative experimental approach for determining the network components of the 2-port antenna model. The new approach involves connecting both ports of the antenna simultaneously to the 2-port VNA via a dual coaxial cable and fully exploits the capabilities of a VNA including calibration and adapter removal. Both approaches are presented in detail and compared. Finally, the effect of ferrite choke beads on the coaxial feed transmission line on the equivalent network is investigated.

A Design of Vertical Polarized Conformal Antenna and Its Array Based on UAV Structure

The designs of conformal antenna and its array usually need to combine with different carrier structures. As for cone or cylindrical carrier, through using of invasive weed optimization (IWO), the conformal array should be the optimized design as the antenna installation space requirements of cylindrical carrier; through adopting the antenna unit miniaturization method, it designs out a conformal antenna and makes it easier to be installed and the omnidirectional circular polarized beam is also realized. As for unmanned aircraft carrier, it designs out the low profile of conformal vertical polarization antenna unit; through using the electric field integral equation (EFIE) and electric/magnetic current combined-field integral equation (JMCFIE) and multilevel fast multipole algorithm (MLFMA), it analyzes the two different characteristics of unmanned aircraft carrier on the influence of antenna performance. The results obtained through experiments and JMCFIE analysis are in good agreement; according to unmanned aircraft carrier, it also designed out the antenna in X/K-band spectrum; through IWO, the antenna array is optimized; the test results show that the array scanning angle can reach the corresponding beam direction.

A novel operation mode for spaceborne polarimetric SAR

A novel operation mode for spaceborne polarimetric SAR, named polarization space-division adding polarization code-division (PSD-PCD) operation mode, is proposed in this paper through combining polarimetric SAR with elevation digital beam-forming (DBF) on receive. In a pulse repetition interval the up-chirp LFM sub-pulse is transmitted with horizontal polarization antenna, and with some delay the down-chip LFM subpulse is transmitted with vertical polarization antenna to realize code division. After every sub-aperture receives returns from ground, SAR system uses range DBF to separate echoes relative to different sub-pulses in order to realize space division. The system PRF is equal to that of single-polarization SAR, and elevation DBF help reduce range ambiguity effectively. Moreover, the main system parameters, including PRF, delay between two sub-pulses, radar equation and ambiguity are analyzed and compared with those of single-polarization SAR. Simulation results demonstrate the feasibility and validity of PSD-PCD operation mode.

Adaptive cancellation of Es layer interference using auxiliary horizontal antennas

Based on a dual-polarization high-frequency wave radar system, an adaptive system using horizontal antennas for the suppression of the Es layer interference (ELI) is described. The data received from the horizontal antennas were correlated with the data received from the Vertically Polarized Antennas (VPAs) to estimate and cancel the interference adaptively in the VPAs. Suppressing the interference after each coherent integration time interval, about 25 dB signal-to-interference ratio is expected with the experimentally derived data.