Dual-Polarized mm-Wave Endfire Chain-Slot Antenna for Mobile Devices

Abstract

This article describes a dual-polarized end-fire antenna array for millimeter-wave frequencies. The antenna consists of a chain-slot-shaped pattern on a mobile phone metal frame. The antenna is fed using a transmission line, which would cause only a negligible capacitive loading of the sub-6 GHz antenna realized on the same metal frame and, therefore, would not significantly degrade its perfomance. This makes colocating the sub-6 GHz and mm-wave antennas in the same, shared volume possible. Measurements indicate that a 4-element array placed within a mobile phone provides a realized gain between 8 and 12.6 dBi for both polarizations across the entire band from 24.5 to 29.5 GHz. The total efficiency of a single element is better than −2 and −3 dB for the whole band for horizontal and vertical polarizations, respectively.

The Role of Millimeter-Wave Technologies in 5G/6G Wireless Communications

“…By utilizing the SIW structure, two dual-polarized endfire radiating elements and their arrays were designed -one is based on the magneto-electric dipole concept [103] while the other is enabled by jointly exploiting the open waveguide and periodic plate loading [104]. In [105], as shown in Fig. 14(b), a chain-slot structure cut out on the frame of the cellular handset, which is fed by vertical and horizontal probes, was used to achieve dual-polarized end-fire radiation with the beam steering capability.…”

Capacitively-Loaded Feed Line to Improve mm-Wave and Sub-6 GHz Antenna Co-Existence

“…11b. This line is used in practice in [37] in which the antenna realization requires a complicated multi-layer structure. The same PCB is used here.…”

“…Fig. 11b shows that the feed line uses only two 0.02 to 0.035-mm thick metal layers, whereas the antennas in [37] require six metal layers. Hence, the non-uniform substrate permittivity may seem unjustified but is required by the antennas.…”

“…Hence, the non-uniform substrate permittivity may seem unjustified but is required by the antennas. More details on the PCB are given in [37].…”

Dual-Polarized mm-Wave Endfire Antenna for Mobile Devices

“…Even though the concept is very promising, only simulations are shown. In [21], a dual-polarized mm-wave module that is partially integrated into the metal frame is presented. However, the module is not physically offset from the metal frame and, therefore, requires the use of the special feed presented in [25], which may be challenging to produce in a flexible PCB.…”