As shown in FIG. 9B, signal transformation circuitry 124b includes differential amplifier 918, frequency multiplier 922, and differential amplifier 926. Signals output by receive antenna 122 may be provided to differential amplifier 918 via lines 916a and 916b. The differential amplifier 918 may amplify the difference between signals received via line 916a and 916b, and may provide the resulting amplified signal to frequency multiplier 922 via line 920. The frequency multiplier 922 may generate output signals whose frequency is a multiple of the frequency of the input signals received via line 920, and may provide the output signals to differential amplifier 926 via line 924a. The differential amplifier 912 may receive input signals via line 924a and ground 924b, and may amplify the difference between the received signals and provide the amplified signals to the transmit antenna 126 via lines 928a and 928b.
In the illustrated embodiment of FIG. 9B, frequency multiplier 922 may be of any suitable type including any of the types described with reference to frequency multiplier 908 shown in FIG. 9A. Each of amplifiers 918 and 926 may be of any suitable type and may be used to induce any suitable amount of gain to the input signals.
