Ultra-wideband, high efficiency oriented RF power amplifier using current source MIC technique for wireless monitoring of obstetrics patient

This paper presents an Ultra-wideband, high-efficiency Class-E power amplifier (PA) using a current source tuner and microstrip inter-digital capacitor (CSTMIC) for UWB radar towards wireless monitoring of obstetrics patients. The proposed Class-E PA contains the CSTMIC, the main PA with Cascode-E operation, and an input-output matching network. The design of a microstrip inter-digital capacitor compensates for parasitic losses into its air gap structure and achieves a wide band of operation. While the MIC integrated current source tuner incurs the loading effect and contributing an Ultra-wideband of operation. The proposed Cascode Class-E PA integrated with CSTMIC is implemented and fabricated using CMOS 65 nm commercial process. The Cascode Class-E PA has achieved a maximum output power of 26 dBm, power added efficiency (PAE) of 63%, gain of 18 dB over the wideband response of 2.1 to 11.7 GHz. In addition, the adjacent channel leakage ratio (ACLR) of -37 dBc and EVM of -47 dB has been measured at a maximum output power of 25 dBm. The size of the fabricated chip is 0.52 x 0.78 mm(2) with consuming less power consumption of 65mW while it occupies less die area as compared to the existing PAs. The performance evaluation of the proposed Class-E PA integrated CSTMIC provides robustness towards design validation for UWB radar in medical applications.