GRF2501 High Gain Ultra-Low Noise Amplifiers Guerrilla RF GRF2501 High Gain Ultra-Low Noise Amplifiers are designed for IEEE 802.11a/n/ac/p applications (5.1GHz to 5.925GHz). The GRF2501 exhibits an outstanding de-embedded 0.80dB noise figure (NF) with excellent gain flatness and high linearity. The Guerrilla RF GRF2501 design's high gain, superior NF, and directivity allow receiver architectures with outstanding cascaded NF and unconditional stability.