7-GHz Inverted-F Antenna Monolithically Integrated with CMOS LNA

Transmitter and receiver antennas monolithically integrated with CMOS LSIs are strongly demanded for reducing the cost of wireless equipment. As the first step toward realizing high-performance antennas on lossy Si substrates, we clarify the design methodology and basic characteristics of inverted-F antennas used for the 7-GHz band corresponding to multi-band OFDM UWB group3 spectrum allocation. An inverted-F antenna along with a low-noise amplifier (LNA) are designed and fabricated using a 0.18-mum mixed signal/RF CMOS process with one poly and six metal layers. Comparisons between measured and calculated antenna gain characteristics are made. Measured antenna gain is about -25 dB in the multi-band OFDM UWB group3 frequency band. Fairly good agreement between measured and designed gains is obtained by taking account of the real geometry of the fabricated chip