Advanced Order Linearizer for Satellite Communications

Linearizer Technology Inc. produces analog predistortion linearizers. Integrated with a power amplifier (PA) and used for SATCOM applications they approach the performance of an ideal amplifier. Limitations of LTIs linearizers are the need for meticulous tuning to achieve the desired characteristics over frequency, and the need for adjustment to match a PAs specific characteristics. LTI has developed an adaptive analog predistorton linearizer (AAPDL) for Ku-band (13.75 to 14.5 GHz) not limited to a satellite channel (36 MHz) that operates with multicarrier signals and all forms of modulation across a 750 MHz bandwidth. LTI proposes to extend its AAPDL technology to Ka- and Q-band. In Phase I, it produced a prototype Ka-band AAPDL covering 27.5 to 31 GHz and the preliminary design for a Q-band version. The Ka-band linearizer is capable of multicarrier operation over its full instantaneous bandwidth. When mated with a PA, it should provide an AM/PM of less than 1 /dB, and an adjacent channel power ratio nears that of an ideal amplifier up to saturation across its operating band. The proposed Phase II effort will develop a AAPDLs for Ka and Q-bands ready for manufacture and demonstrate their operation with commercial PAs.