Broadband and Efficient Envelope Amplifier for Envelope Elimination and Restoration/Envelope Tracking...

Area of Science:

• Electrical Engineering
• Wireless Communications
• Signal Processing

Background:

• Transmitter energy efficiency is critical for wireless devices, with envelope tracking and restoration being common optimization methods.
• Increased bandwidth demands necessitate wider bandwidth envelope modulators (250-500 MHz+).
• Existing methods like hybrid envelope tracking modulators face limitations, including electromagnetic interference from pulse width modulation (PWM).

Purpose of the Study:

• To evaluate amplifiers with input signal quantization (AISQ) as a viable alternative to hybrid envelope tracking modulators.
• To develop an optimization approach for AISQ characteristics minimizing power loss for signals with Rayleigh envelope distribution.
• To determine optimal quantization levels and analyze the energy efficiency of AISQ.

Main Methods:

• Developed an optimization approach for AISQ based on minimum power loss for signals with Rayleigh envelope distribution.
• Determined optimal quantization levels for AISQ.
• Calculated and compared the energy characteristics of AISQ with a Class B amplifier.

Main Results:

• AISQ demonstrates significant power loss reduction: 1.66x for two-level, 2.4x for three-level, and 3.0-3.7x for four-five level quantization compared to Class B amplifiers.
• Optimized AISQ achieves competitive efficiency with hybrid envelope tracking modulators.
• AISQ avoids the electromagnetic interference associated with PWM found in other modulator types.

Conclusions:

• AISQ presents a promising, energy-efficient alternative for wireless transmitters, particularly for high-bandwidth applications.
• The developed optimization strategy effectively reduces power loss in AISQ.
• AISQ offers a competitive and cleaner solution compared to existing envelope tracking and modulation techniques.