Power Efficient Software Defined Radio (SDR) Mobile Architecture Technology for Handheld Devices

ABSTRACT: In this proposal we describe a highly flexible, ultra low-lower power GNSS receiver. By building the receiver from the ground up with flexibility and ultra-low voltage in mind, we are able to achieve a 5-20x improvement in energy-efficiency while providing support for a wide variety of GNSS codes. The proposed flexible code generator is able to efficiently support C/A, L2C, M, P, and L5 codes. The system firmware will execute on low-voltage, low-power RISC processing cores operating in parallel. A novel current-mode correlator provides long correlation lengths (>65,000 bits) while maintaining energy-efficiency and a small silicon footprint. The Phase 2 effort is divided into two fabrication efforts: a proof-of-concept (PoC) microchip and a prototype microchip. The proof-of-concept microchip will be designed, fabricated, and tested in order to inform the design of the prototype. The PoC chip will contain test structures and/or initial designs for all of the experimental portions of the system. The prototype chip will be a full low-power GNSS receiver, which will be capable of providing a live demonstration. This project is a collaboration with the University of Michigan Integrated Circuits Laboratory, who has extensive experience with fabricating advanced integrated circuits. BENEFIT: The proposed receiver will achieve a 5-20x improvement in energy-efficiency over existing solutions while providing support for a wide variety of GNSS codes. Systems containing this GNSS receiver will have reduced battery and thermal requirements, making them smaller and operate longer in the field. Low-power operation is particularly useful for handheld devices, autonomous vehicles, and asset/fleet tracking systems, where energy sources are limited. The flexible code generator supports C/A, P, M, L1C, L2C, L5, and Galileo E1 in a single compact module, and also allows new codes to be programmed into the system as they are created, thereby adding lifetime to the system. The current-mode correlation circuit can simultaneously correlate tens of thousands of bits in compact, low energy form factor, allowing fast acquisition of weak or jammed signals, or in C/A denied scenarios. In general, almost all systems currently containing a GNSS receiver would benefit from the technologies developed in this proposal.