COMPACT MULTIBAND MIMO ANTENNA FOR NEXT GENERATION USB DONGLE APPLICATIONS

Abstract

A compact multiband multiple‐input multiple‐output (MIMO) antenna with an embedded chip inductor is proposed for next generation universal serial bus (USB) dongle applications. The proposed MIMO antenna consists of a longer strip with an embedded chip inductor and a shorter radiating strip. The longer radiating strip with a 15‐nH embedded chip inductor has a length of only about 34 mm (about 0.08 wavelength at 0.77 GHz), but it supports a wide resonant mode for long‐term evolution band 13 (LTE Band 13; 0.746–0.787 GHz) and wireless broadband band (WiBro band; 2.3–2.4 GHz) services. The shorter radiating strip has a length of 12 mm (about 0.1 wavelength at 2.0 GHz) and provides a wide resonant mode at about 2 GHz for wideband code division multiple access band (1.92–2.17 GHz) operation. The two radiating strips occupy a small printed area of about 500 mm2 on the system circuit board of a USB dongle. The proposed MIMO antenna has an isolation of approximately 17 dB at LTE band 13 and the envelope correlation coefficient (ECC) of the two antennas is less than 0.4 over the whole LTE band 13. To evaluate the performance of the proposed antenna, key performance parameters such as the total efficiency, ECC, mean effective gain (MEG), and the MEG ratio are analyzed.