A tri-band Multiple-input-multiple-output (MIMO) antenna system for LTE 700, LTE2500 and GSM 1800/1900 mobile handset application is presented. The whole system consists of four identical 3-D IFAs (inverted F antenna) folded on FR4 cuboids. Without any special designed decoupling structures, the measured isolation among antenna elements is higher than 20dB in the low and upper bands, even in the middle band, the isolation is higher than 13.7dB. Reflection coefficient, correlation coefficient, gain and radiation pattern are also presented. Acceptable agreement between the antenna models with and without plastic housing, battery and LCD screen demonstrate that the proposed antenna is a competitive candidate for mobile handsets.

A compact dual-band MIMO (Multiple-Input-Multiple-Output) antenna system for LTE33 band, LTE 2300 and ISM 2.4GHz applications is presented. The whole system consists of four identical folded 3-D IFAs (inverted F antenna) mounted on nonmetallic cuboids. By using the radiation pattern diversity of the antenna elements, higher than 15dB isolation among the antenna elements and low correlation coefficient (CC<0.3) are achieved without any specially designed decoupling structures. Its gain and radiation pattern are elucidated.

Instrumental variable (IV) filters designed for range sidelobe suppression in multiple-input multiple-output (MIMO) radar suffer from Doppler mismatch. This mismatch causes losses in peak response and increases sidelobe levels, which affect the performance of MIMO radar. In this paper, a novel method using the component-code processing prior to the IV filter design for MIMO radar is proposed. It not only compensates for the Doppler effects in the design of IV filter, but also offers more virtual sensors resulting in narrower beams with lower sidelobes. Simulation results are presented to verify the effectiveness of the method.