Already one of the most widespread of the low-power, wide-area protocols, LoRa has seen some recent developments that promise to further the protocol’s adoption. A new link-layer specification aims to help facilitate worldwide deployments and an innovation in the packaging of passive components promises to help reduce implementation size. Together they can help increase the momentum of LoRa adoption.
The new specification package, LoRaWAN TS1-1.0.4 Link Layer (L2) Specification, contains several elements that together define a reference implementation that can serve as a starting point for product development. In addition to the L2 specification itself, the package provides a pathway for design certification. This pathway starts with the TS009 Certification Protocol and defines both a certification program and requirements document. In addition, a LoRaWAN certification test tool (LCTT) update for pre-certification and regression tests is included. The package also includes reference code for end devices that meets certification requirements.
The specification update includes numerous clarifications to help ensure interoperability among devices following the standard. This clarification aims to help simplify the development, deployment, and management of LoRaWAN networks by eliminating ambiguities and possible confusion in interpretation. New security features have also been added to augment the protocol’s inherent strong security. These include clarifications for handling counters and persisted parameters.
Figure 1 LoRaWAN already sees widespread adoption, which its latest Link Layer specification aims to augment. Source: LoRa Alliance
Specifications alone are not enough to ensure a technology’s adoption, however; products that support rapid development are also required. For the LoRaWAN, such products are becoming increasingly available. Senet, Inc., for instance, has recently partnered with distributor Symmetry Electronics to offer modules, gateways, and sensors that work with Senet’s carrier-grade LoRaWAN network. In addition, Symmetry customers can access the Senet network during development to onboard and test their systems during prototyping and production.
Passive components are also seeing innovative engineering for work with LoRa systems. Johanson Technology has recently released an integrated passive device (IPD) that combines all the front-end capacitors and inductors needed to go between a Semtec LoRa chipset and an antenna into a 2.0×1.25 mm SMT package. This includes an impedance matching network, balun, and filter that might otherwise require up to 40 RF components and is built using low-temperature co-fired ceramic (LTCC) manufacturing technology.
Figure 2 A single SMT package contains all the passive circuitry needed to implement an impedance-matched balun filter for LoRa. Source: Johanson Technology
The IPD approach offers developers several advantages. For one, it is some 40% smaller, as well as lighter, than an equivalent circuit made of discrete devices, allowing more compact IoT device design. Further, the integrated implementation provides higher reliability by eliminating interconnect traces and vias on the PCB. Variability in circuit operation is also reduced as a result of the integration.
Innovations like the IPD are continually appearing in the LoRaWAN market, helping propel the protocol’s further adoption. LoRa’s low data rates mean that the approach is not the best match for every IoT application, but for sensors and other systems where low power and long range are more important than data capacity, these kinds of innovations can only further the momentum of the technology’s adoption worldwide.
Rich Quinnell is a retired engineer and writer, and former Editor-in-Chief at EDN.