ACLYS employs highly advanced architecture and signal processing design to meet and exceed the challenging GPS requirements of today’s mobile device designer.

RF Front-end and Co-processor On One Die
By using mixed signal RFCMOS technology, CellGuide created ACLYS as a monolithic, single-die solution with both an RF front-end and GPS coprocessor.

As a single-die chip, ACLYS is the natural evolution of its predecessor, the CGX5900, which used a 2-chip architecture.

Proprietary Signal Processing Technology
ACLYS contains CellGuide’s unique, proprietary signal processing technology. This technology enables ACLYS to track satellites in view using a sky snapshot (“snap time”) of only a fraction of a second. This means that while in tracking mode, much less power is consumed because the snap, which is the most energy intensive phase of the tracking process, has been limited to only a fraction of the system duty cycle.

The quick snap time is possible because CellGuide’s signal processing technology employs unique algorithms that reduce the number of calculations required. This is in contrast to other (software or hardware) GPS solutions that require far more calculations, processing, and additional dedicated silicon, than ACLYS.

ACLYS’ quick snap time also dramatically reduces the power consumed by its RF front-end. ACLYS can control its RF front-end, and shut it down between snaps to reduce power consumption even further.

Fewer Calculations=Fewer Gates
The other advantage of CellGuide’s unique signal processing techniques, is that far fewer gates are needed to implement the co-processor. This reduces the power consumption even further. It also enables the ACLYS die to fit into a very small 5 mm x 5mm QFN32 package.

TTFF is also shorter because the snap and signal processing are completed faster. MIPS and memory requirements within the host ACPU are also minimized. In tracking mode, ACLYS runs quietly in the background, while LBS and other applications run simultaneously on the host device.

A Perfect Balance of Hardware and Software
Traditionally, GPS basebands have been hardware devices with fixed firmware. In addition, some software-based solutions have surfaced but have proven ineffective for processors typically integrated in consumer devices. ACLYS is a hybrid hardware and software solution designed to take advantage of the best of both approaches.

ACLYS hardware offloads certain tasks from the host software so that only minimal host MIPS are required. The CellGuide host software runs in the background while other applications run smoothly on the host processor. The CellGuide software uses only a fraction of the MIPS required by other software basebands. Consequently, it can run even on today’s entry-level mobile ACPU’s or DSP’s.

The CellGuide host software has flexibility that enables its optimization for a wide variety of GPS use-cases. This flexibility is difficult or impossible to match for hardware chipsets with their fixed firmware. The CellGuide host software can also be provided with customer-specific API commands tuned to a device’s unique requirements. Applications such as personal navigation, emergency use (E911/E112), vehicle/asset tracking, pedestrian use, or others can uniquely benefit from the flexibility afforded by a software approach. This also ensures optimal power usage and efficiency for each use case.

GPS and AGPS Support
ACLYS is able to accept data (ie. last position, almanac, ephemeris, time) which is available from the host, or it can operate completely autonomously. As a result, ACLYS is able to take advantage of even partial assistance data to minimize the energy required to lock-on and track satellites in any given situation.
   
Advanced Multipath Control
In order to ensure navigation accuracy in even the toughest dense urban or indoor environments, ACLYS uses advanced multi-path mitigation algorithms.  

Designed for Fast Integration
The ACLYS hardware uses an SPI bus for integration with a wide variety of processors. It accepts a wide range of TCXO frequencies, from 10 to 40 MHz, in order to guarantee compatibility with the existing TCXO on the host board.

The Cost Advantage
Leveraging the host’s processor results in a high-performance, low cost GPS baseband solution. Instead of duplicating the ARM or DSP functionality that already exists on the host board, ACLYS takes advantage of a fraction of the host’s ARM or DSP resources to complete the baseband solution, thereby minimizing the cost of dedicated GPS hardware.

Consequently, the dramatically lower cost of ACLYS is suitable for mass-market devices, yet its performance is able to meet the toughest mobile device requirements.