A Roundup of GNSS Receivers Bringing Pinpoint Positioning
Vehicles and wearables alike require increasingly precise positioning technology—and this innovation is often fine-tuned starting with GNSS receivers.
Two industries that are ever vying for the latest advances in spatial positioning technology are the automotive and wearables industries.
Overview of a GNSS system. Image used courtesy of u-blox
To this end, one technology that has been invaluable in both fields is global navigation satellite systems (GNSS). As a testament to this demand, this fall has seen a huge influx of new GNSS devices reach the market, with releases from the likes of STMicroelectronics, u-blox, and Broadcom.
In this article, we’ll take a look at the new releases from these companies, compare the hardware-level innovations at play, and assess what these releases can tell us about the industry’s need for new positioning technology.
ST Brings Triple-band Positioning on a Single Chip
Earlier this month, STMicroelectronics released a new automotive GNSS chipset that introduces an integrated IMU for use in dead reckoning. Now, just a few weeks later, ST has brought another GNSS product to market: the STA8135GA.
ST claims that the STA8135GA is the first of its kind to integrate a triple-band positioning measurement engine in a single GNSS receiver chip. Triple-band positioning is a GNSS technique that uses GPS signals at different frequencies to simultaneously track a number of satellites. This technique can improve positioning performance in difficult environments such as tunnels or forests.
A highly accurate technique, triple-band positioning has historically been limited to physically large or expensive receivers. Now, with the STA8135GA, ST is offering triple-band positioning in a 7 mm x 11 mm x 1.2 mm package.
Block diagram of the STA8135GA. Image used courtesy of STMicroelectronics
Beyond triple-band performance, the new chip can perform other positioning techniques such as standard multi-band position-velocity-time (PVT) and dead-reckoning. According to the datasheet, the STA8135GA is built around a single Arm Cortex M7 core, operating at a maximum clock frequency of 314 MHz. This core is supported by 16 KB of I-cache,16 KB of D-cache, and 256 KB of system RAM.
u-blox Combines Untethered and Automotive Dead Reckoning
The next GNSS solution to discuss comes from u-blox with its new NEO-M9V GNSS receiver.
u-blox claims it has created the first GNSS receiver to offer both untethered dead reckoning (UDR) and automotive dead reckoning (ADR) capabilities. Similar to the ST release, u-blox is able to achieve UDR through the use of integrated IMUs; however, the Switzerland-based company offers an in-house ADR technique that factors vehicle speed into its sensor fusion algorithm. Offering both UDR and ADR on the same module heightens performance and maximizes design flexibility for the end-user, according to u-blox.
The Neo-M9V comes in a 12.2 mm x 16 mm x 2.4 mm package. Image used courtesy of u-blox
Beyond this, the NEO-M9V is built on u‑blox’s M9 GNSS technology platform, which allows the device to track up to four GNSS constellations simultaneously. Together, these techniques equip the device to achieve meter-level positioning performance for applications like fleet management and micro-mobility.
Broadcom's "World’s Lowest Power L1/L5 GNSS Receiver"
Finally, in September, Broadcom introduced its own GNSS receiver to market, the BCM4778.
The BCM4778 GNSS receiver for wearables. Image used courtesy of Broadcom
The BCM4778 is a dual-frequency L1/L5 GNSS receiver chip designed for consumer electronics and wearables. That said, the primary design concerns for this device are power consumption and size.
Built on 7nm CMOS technology, the BCM4778 offers a power consumption of 4 mW when using the L1 band only and 6mW when using L1+L5 simultaneously. According to Broadcom, these power specs make the BCM4778 the lowest power L1/L5 GNSS receiver chip for wearable applications. In terms of size, this chip is 35 percent smaller than its previous generations.
Beyond this, the BCM4778 offers fully integrated LNAs for both the L1 and L5 bands, further helping reduce the BOM and footprint for the end-user.
Positioning Popularity on the Rise
These new positioning technologies from ST, u-blox, and Broadcom affirm a recent report that suggests a mounting demand for GNSS receivers: by 2028, the market for high-precision GNSS receivers is projected to reach $5.54 billion, according to Vantage Market Research.
The increased focus on positioning devices—and GNSS augmentation services as a result—is also cropping up globally. In fact, u-blox and SoftBank Corp. recently signed an agreement to develop GNSS devices and expand GNSS service areas in Japan, Europe, and the U.S.