Farid Shirinfar

A fully integrated 22.6dBm mm-Wave PA in 40nm CMOS

A fully integrated 60GHz CMOS PA with a PSAT of 22.6dBm is presented. To our knowledge, this is the highest reported PSAT at mm-waves in standard CMOS. To achieve a high power level, 32 differential PAs are combined through a network of transmission lines, Wilkinson combiners, and a multi-port argyle transformer. This method of combining minimizes loss while implementing a low impedance load (~12Ω) at the drains of each of the last stage PAs. Electromigration and other reliability issues are discussed.

A compact millimeter-wave energy transmission system for wireless applications

A compact energy transmission system in 40nm standard CMOS is presented. The system consists of a 60GHz VCO followed by a quad-core power amplifier as transmitter and an RF-to-DC converter as receiver. The total power delivered by the quad-core PA to its four 50Ω loads is 24.6dBm. The receiver is a complementary cross-coupled rectifier with a measured efficiency of 28% while supplying 1mA of current. The system can support amplitude and frequency modulations and beam-forming capabilities for wireless applications with minimal front-end complexities.

A multichannel, multicore mm-Wave clustered VCO with phase noise, tuning range, and lifetime reliability enhancements

Clustering and multi-core transformer coupling techniques are presented to improve phase noise, tuning range, and reliability of a mm-wave VCO. A proofof-concept design targeting the WiGig protocol is shown. Each cluster of VCOs covers one channel resulting in better phase noise performance. Multicores of VCOs with uncorrelated noise are combined using transformers to further enhance phase noise and combat the voltage swing reliability issues. Furthermore, due to realization of multiple inductive elements in parallel instead of one small inductor, this approach bypasses Q-degradation of small inductors (<;50pH). The VCO achieves a phase noise of -101.8dBc/Hz at 1MHz offset with over 12.6% tuning range (50.7GHz to 57.5GHz) and an FOM of -183dB/Hz.

A Compact 60-GHz Wireless Power Transfer System

The first reported full-system 60-GHz wireless power transfer (WPT) solution that can power batteryless and charge coil-free compact WPT devices is presented. The system is fabricated in a 40-nm digital CMOS process and an inexpensive packaging material. In the rectenna (RX), a grid antenna is integrated with a complementary cross-coupled oscillator-like rectifier. At a 4-cm spacing from the transmitter (TX), the RX harvests energy at a rate of 1.22 mW with a 32.8% efficiency, which is significantly higher than the prior state of the art. A novel theoretical analysis of the rectifier operation is presented that formulates all key specifications. The TX is equipped with a quad-core PA that produces a saturated output power (Psat) of 24.6 dBm, which is the highest power delivery in digital CMOS at millimeter-wave bands. The TX peak power-added efficiency is 9.4%. In the TX, a 4 × 8-way differential power combining and a binary-tree architecture are implemented. The designed 2 × 2 grid array antenna helps the TX produce 35.3-dBm peak equivalent isotropically radiated power. The results of the performance characterizations of the full-system and all individually fabricated blocks are reported. The quadcore PA supports power control and beam steering. A four-port TX antenna is designed that shows a 70° steering range in simulations.

High-Efficiency Millimeter-Wave Energy-Harvesting Systems With Milliwatt-Level Output Power

The output power level and the power conversion efficiency (PCE) rate of the energy-harvesting systems are vital factors in realizing effective millimeter-wave wireless power transfer solutions that can power battery-less and charge coil-free smart everyday objects. Two 60-GHz energy harvesters that use a tuned complementary cross-coupled oscillator-like rectifying circuitry in 40-nm digital CMOS process are presented. They harvest energy at power rates and peak PCE levels in excess of 1 mW and 30%. These figures are significantly higher than those of the prior art. In one design, two rectifier stages are in a cascode configuration to produce higher dc output voltage levels at the low-current regime. Novel theoretical analyses of the unique rectifying circuitry of the single-stage and two-stage cascode harvesters are presented, which formulate all of the key specifications.

Adaptive Gain and Phase Adjustment for local linearization of Power Amplifiers of micro/mm-wave Phase arrays

A wideband, local Power Amplifier (PA) linearization technique is presented. The proposed Adaptive Gain and Phase Adjustment (AGPA) local linearization technique compensates for both AM-AM and AM-PM distortion of PA for large channel bandwidths of hundreds of megahertz. A 60GHz PA designed in a 28nm CMOS process is designed and measured. AGPA improves the OP1dB of the stacked PA by 2.8dB from 9.5dBm to 12.3dBm and reduces the IM3 products by 3dB with a tone spacing of 200MHz at 8dBm output power.