Figure 4: Graphene IC measured as RF receiver.
(a) Output spectrum of graphene receiver with 900 nm gate length. RF input signal was −20 dBm at 4.3 GHz and LO input signal was −2 dBm at 4.2 GHz. Down converted IF output signal at 100 MHz (fIF=fRF−fLO) was −30 dBm. (b) Normalized output power of the fundamental tone (P1F), the second harmonic (P2F) and the third harmonic (P3F) as a function of RF power (PRF), showing no gain compression up to −10 dBm PRF. (c) Normalized output power as a function of LO frequency. (d) Normalized output power as a function of RF. (e) Measured waveforms of RF input signal amplitude modulated at a rate of 20 Mb s−1, IF output signal and restored binary code after rectifying and low-pass filtering IF signal. (f) A screenshot of receiver output waveforms taken from the oscilloscope, with LO power of −2 dBm at 4.2 GHz. The original bit stream comprising three letters (24 bits) was recovered by graphene receiver with very low distortion. The circuit was measured in air.
