A module includes a substrate including an IC disposed on an upper surface side thereof. The IC includes a modulation circuit unit arranged to modulate a baseband signal into an RF signal and a demodulation circuit unit arranged to demodulate an RF signal into a baseband signal. The substrate includes a first wiring layer provided on the upper surface side, a second wiring layer disposed on a lower surface side of the first wiring layer, and an insulator layer disposed between the first wiring layer and the second wiring layer. A baseband signal-use wiring pattern is provided in the first wiring layer, an RF signal-use wiring pattern is provided in the second wiring layer, and on one surface of the insulator layer, a substantially flat-plate ground electrode pattern is arranged to cover substantially an entire surface. A balun is provided in the second wiring layer.