The IoT is a conglomeration of many vertical markets, including home and building automation, meter reading and sensor/actuator monitoring. Wireless connectivity is fundamental to the IoT and LPWANs are emerging as a key enabler for many of the applications now contained within the IoT.
By selecting a flexible and programmable single-chip solution, developers are better placed to meet the challenges of the IoT in a cost-effective and power-efficient way. This can be achieved using the AXM0F243, a software-programmable System-on-Chip (SoC) solution that supports low power, long-range IoT applications including Automatic Meter Reading (AMR), security and home and building automation.
Despite their origins in more complicated radios, Software Defined Radios (SDRs) provide tangible benefits for a simpler Low-Power Wide-Area Network (LPWAN) device. Since most protocols don’t attempt to modulate data rates or power levels, less complicated and slower processing is acceptable. The requirements on the analog front end, ADC and DAC and microcontroller resources are all optimized toward lower cost and lower power. LPWAN SDRs can be reconfigured either at run time or in between messages from one protocol stack and switch to another protocol stack. LPWANs typically don’t exchange data all that often so it’s realistic to do multi-protocol.
Another key benefit is that an OEM can standardize their hardware platform with one System on Chip (SoC) part number and differentiate their platforms through software and/or minimal hardware modifications for RF components.
One key disadvantage in Software Defined Radios systems is the antenna interface. Wide band or multi band antennas are costly and difficult to design. This is a key reason why the more complex Software Defined Radios systems are not used more often commercially. Thankfully most LPWAN protocols focus on using ISM bands, which means the bands more or less overlap between the various protocols, allowing a lower cost and simpler antenna interface to be designed.
Wireless technologies targeting the LPWAN application space cover a wide range of frequencies, from 27 MHz up to 1050 MHz. In order to realize a single design that can address many different IoT applications using various LPWAN protocols, the transceiver would need to be capable of operating over the entire range. In addition, the protocols running in firmware would require a capable microcontroller.
Bringing these two functional elements together into a single device creates a flexible solution that is both cost-optimized and more power-efficient than a two-chip approach. As it is largely software-defined it provides manufacturers with a platform that can be easily adapted to meet the demands of a wider range of applications using different wireless protocols.
Many IoT endpoints operating over an LPWAN must limit the amount of data they exchange wirelessly, which is putting more emphasis on edge processing; enabling the endpoint to process data locally and take action without referring to a cloud platform. To support this, the processing performance of the any solution needs to be finely balanced between power and performance and that is where the AXM0F243 fits in. With a proven narrow-band AX5043 transceiver and 32-bit Arm® Cortex®-M0+ core, the AXM0F243 supports nearly all Sub GHz protocols- whether Proprietary RF or standards-based. The software programmability of the radio core also makes it possible for manufacturers to reuse a common hardware design for products that have different software loaded.
Learn more about the AXM0F243 here.
Visit Us at Embedded World
Dan Clement will present his technical paper “How a Software-defined Radio Enables Diversity in IoT Endpoint Design” at Embedded World.
Location: Conference Counter NCC Ost.
Date: February 27, 2019
Time: 11:30- 12:00 PM
