Concurrent dual-band access GaN HEMT MMIC amplifier suppressing inter-band interference

A concurrent dual-band GaN HEMT MMIC amplifier has been developed for next-generation wireless communication systems. To increase information quantity, a carrier-aggregation technique that uses two or more bands for one information block will be employed at super-high-frequency bands. Efficiency and linearity for general dual-band amplifiers are strongly degraded in concurrent operation due to cross- and inter-modulation distortion between each band. To suppress those, inter-band interference rejection circuits are embedded in the proposed amplifier circuit configuration. Suppression of cross- and inter-modulation distortion was confirmed for a fabricated 4-/8-GHz-band GaN HEMT MMIC amplifier during concurrent operation.