What is Snapshot GPS Receiver Technology?

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A Snapshot GPS Receiver (or “Snapshot Receiver” for short) is a unique class of receiver that is implemented mainly in software. To see how Snapshot GPS receiver works, we need to understand the basic architecture of a hardware GPS receiver.

 

A typical GPS receiver system consists of a GPS antenna, a Radio Frequency (RF) front-end and a baseband processor.

 

Essentially, the GPS antenna is used to receive and amplify the weak GPS signals from the satellites. The RF front-end is then used to further amplify the weak signal from the antenna and digitize it for processing. The baseband processor decodes the digitized signals and performs a series of mathematically intense signal processing algorithms to calculate position, velocity and time (“PVT”).

 

GPS front-end & baseband processor

 

Until recently, the RF front-end and the baseband processor used to be sold as two separate Integrated Circuits (IC). Nowadays, the majority of the vendors have combined the two IC’s together in one single package (commonly known as “GPS Chipset”) to make it smaller and easier to manufacture.

 

GPS front-end & baseband processor

 

Software based GPS receiver (or “software GPS receiver” for short) technology is an entirely different approach where the functions of the baseband processor are replaced and performed by a general purpose microprocessor. The benefits of detaching the RF front-end from the baseband processor are plentiful. First, the microprocessor can be located locally near the RF front-end or at a server connected remotely via the internet to take advantage of the thousands or even millions of times more powerful processing power. Additionally, since the baseband processor is responsible for some very mathematically intense signal processing algorithms, by off-loading these mathematically intense calculations to a remote server, a significant amount of energy can be saved. Lastly, new features, improved functionalities or even individual customer’s specifications can easily be implemented using software based GPS receiver whereas, in comparison, traditional hardware based GPS chipset can never be updated during the product life cycle.

 

The principal advantage of a software-based GPS receiver is to eliminate the baseband processor to lower the power consumption and to extend product life cycle. However, traditional software based GPS receiver technology requires a significant amount of digitized GPS signals data (2+ MByte/Second) to be sent to a microprocessor for processing. Until the introduction of our Snapshot GPS Receiver Technology, the only way to handle the high speed data and process it in real time was to employ a high performance microprocessor that has very high communication and processing speed thus increasing the overall power consumption, as a consequence, it defeats the purpose of using a software based GPS receiver in the first place!

 

Our Snapshot GPS Receiver technology addresses the high power consumption problems that are associated with the current chipset and traditional software GPS receiver technologies.

 

The power of our Snapshot GPS Receiver technology lies with its ability to compute a GPS position using as little as 2ms (2 milliseconds) or 4 KBytes of GPS signal data. Since the circuitry only needs to be turned on for such a short period of time, our Snapshot GPS Receiver uses negligible power to operate. Since acquiring satellites is a somewhat delicate matter for GPS receivers, when the receiver is operating in a downtown corridor or under dense foliage where open sky can be intermittently blocked by surrounding high rise buildings or heavy tree canopy, the user has full control to instruct the Snapshot GPS Receiver to collect more than 2ms of GPS signal data to compensate.

 

In addition to the numerous benefits mentioned above, our Snapshot GPS Receiver technology can operate in real-time or off-line modes.

 

When operating in real-time mode, our Snapshot GPS Receiver works very similar to a GPS chipset where the RF front-end will collect the GPS signals data then sends it to our server for processing. Using our advanced patent pending processing algorithms, a GPS position can normally be achieved around 100ms or so.

 

When operating in off-line mode, our Snapshot GPS Receiver utilizes a “Store Now and Process Later” approach to capture and store the GPS signals data for future processing. The mathematically intense signal processing are off-loaded to our remote server and performed sometime in the future. The “Store Now and Process Later” approach is ideal for applications that may not require real-time GPS positions or platforms that do not have sufficient resources to handle complex GPS algorithms. Ultra low power applications such as wearables, Internet of Things (IoT), people/animal/asset tracking, geotag, event data recorder (also known as the “blackbox”) and client/server apps are just a few examples.

 

Our Snapshot GPS Receiver Technology offers the benefits of ultra low power consumption, ultra fast positioning and uncomplicated design. It is the next generation GPS receiver technology with the best performance and flexibility that no current GPS chipset receiver technology can match.

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