LTE/Sub-6GHz/MMW Antenna Co-design for Mobile Phones with Front-Side Direction MMW Beam Switching Based on Chassis Surface Waves

A co-design of 4G LTE, Sub-6GHz and MMW antennas in mobile phones with MMW beam switching ability in the front-side direction is proposed. By selecting MMW antenna elements and exciting the chassis surface waves, switchable MMW beams are achieved in the front-side direction. The LTE and Sub-6GHz antenna share a part of the antenna branch and have six resonant modes. The interdigital capacitor (IDC) is employed to be the ground of the MMW antenna, which has a slight impact on the LTE and Sub-6GHz antennas. For the LTE and Sub-6GHz antennas, the band of -6 dB cover 0.704-0.96 GHz, 1.71-2.69 GHz and 3.3-5 GHz. For the MMW antenna, the band of -10 dB cover 26.5-29.5 and 37-40 GHz. A beam steering range of 90° is realized both at 28 and 38 GHz, featuring a gain exceeding 8.8 dBi.