Samsung boosts antenna performance

Samsung boosts antenna performance by 7.6 dB with CK MEMS SmarTuner

Smartphone antennas are placed along the edges of the phone to maximize radiation efficiency.  However, the close proximity of head or hand can significantly alter the antenna’s resonant frequency, and consequently have a negative impact on the antenna’s performance.   To partially address this challenge, Closed Loop Impedance Matching (CL-IM) algorithms have been developed to dynamically reduce the reflected power at the feed point of the antenna.   Unfortunately, CL-IM does not correct the antenna’s resonance, which means the antenna itself still suffers large efficiency losses.

The optimum solution is to dynamically correct the antenna’s resonant frequency to compensate for environmental factors, such as the presence of head or hand.   Doing so simultaneously eliminates most of the impedance mismatch losses at the antenna feed point.  This technique is called Closed Loop Aperture Tuning (CL-AT).   CL-AT requires the ability to accurately adjust the electrical length of the antenna with a low-loss tuner such as the Cavendish Kinetics (CK) MEMS SmarTuner.  CK’s SmarTuner has 32 different capacitive states, and can be directly connected to the aperture of the antenna.

Samsung used the CK MEMS SmarTuner, combined with internally developed CL algorithms, to create Samsung Smart Antenna Technology (SSAT).  SSAT is a revolutionary solution to head/hand losses, and was recently demonstrated on a Samsung smartphone that supported LTE bands 5/8/20 and WCDMA band 8.    Using a left flat hand phantom, Samsung obtained between +2.3 and +7.6 dB  TRP boost depending on frequency band. Samsung presented its results at APS 2018  in July.   This paper can be downloaded from APS 2018 or IEEE website (soon).