Single-Chip Two Antennas for MM-Wave Self-Powering and Implantable Biomedical Devices

Implantable biomedical applications arise the need for multi-band sensors with a wideband frequency channel for RF energy harvesting operation. Using a separate antenna for energy harvesting can simplify device circuit complexity and reduces operation frequency bands interference. This paper demonstrates the design of single chip with two separate integrated antennas for implantable biomedical applications. The two antennas have different structures with orthogonal polarization to achieve low mutual coupling and negligible interaction between them. The first antenna is a multi-band meander line (MBML) designed for multiple channels data communication, with quad operating bands in the MM-wave range from 22-64 GHz with area 1150 × 200μm2. The second antenna is a wideband dipole antenna (WBDA) for RF energy harvesting, operates in the frequency range extend from 28 GHz to 36 GHz with area 1300×250μm2. The proposed antennas are designed by using high frequency structure simulator (HFSS) and fabricated by using UMC180nm CMOS technology with total area 0.55 mm2. The MBML frequency bands operating bandwidths can reach 2 GHz at impedance bandwidth ≤ -10 dB. While, the WBDA antenna has gain -2 dB over the operating band extend from 28 GHz up to 36 GHz. The antenna performance is simulated separately and using the human-body phantom model that describes layers of fats inside body, and shows their compatibility for in body operation. Die measurements is performed using on wafer-probing RF PICOBROBES and shows the matching between simulation and measurement values.