Mobile phone performance improvements using an adaptively controlled antenna tuner

Mobile phone output power and radiation efficiency are degraded by large mismatches, due to compact narrow-band antennas and the influence of the user´s hand position. This paper presents a 5×5 mm² multi-band multi-mode adaptive antenna tuning module that counteracts antenna impedance mismatch. The module increases phone output power by 1.2 dB on average and 10 dB maximum, once combined with four different commercially available phones in a load-pull setup. The measured average total radiated power (TRP), of one of these phones with adaptive tuner, improves by 2.2 dB for free-space condition and 1.9 dB for user interaction. The measured maximum TRP improvement is 6.8 dB.