Walnut can help design and build your IoT infrastructure for tracking, sensing and device control.
From the device through to server-based or serverless message processing and analytics, we have experience delivering complete IoT solutions.
Get in touch to discuss your next IoT project.
The IoT technology space is diverse and offers multiple standards to choose from depending on your devices and applications.
Depending on the power and processing budget, devices may use short-range radio standards to connect to a local gateway. For remote or standalone applications, devices may use LTE or newer, narrowband standards to connect directly to the internet.
MQTT is a popular publish/subscribe data protocol, which provides for intermittent connectivity on both device and server sides. Many other protocols exist with their own tradeoffs.
On the server-side, messages may be collected and processed by a traditional application stack. Increasingly however, serverless platforms such as Amazon AWS offer a low-cost, scalable approach to processing and storing IoT data.
Walnut often recommends a hybrid solution where the serverless platform handles intake and stores messages until an application can process them.
IoT applications are diverse, and devices may be located anywhere from busy urban environments to remote rural locations. Device location, required bitrate, carrier support and power budget will all drive the choice of communications technology.
In an urban environment, IoT devices may leverage Zigbee, Bluetooth or WiFi networks. Further afield, a modem will be needed that supports LTE or one of the emerging low-power, narrowband standards.
LTE is widely available and supports very high data rates, and the expense of power consumption.
LTE is a good choice where high bitrate is needed and power is available. The default cellular technology in most countries, chipsets are widely available and can often support complete internet connectivity.
LTE-M is a low-power radio standard developed by 3GPP, offering data rates up to 7Mbps (up).
LTE-M is a good IoT choice where higher data rates are needed, but at reduced cost compared to a complete LTE modem. Compatibility with LTE infrastructure has driven rollout among carriers.
NB-IoT is a narrowband radio standard developed by 3GPP, offering data rates up to 159kbps (up).
NB-IoT is a good choice for very low-power solutions and has excellent penetration, supporting indoor applications. Carrier support is good and growing worldwide.
LoRa is a proprietary low power, long-range radio specification which supports battery-powered devices with a range of up to 16km.
LoRa is ideal for receiving low bitrate data from sensors over large sites such as farms and industrial sites, and is licensed for use in most countries.
Sample LTE modem board
This is an LTE hat from WaveShare designed for a Raspberry Pi. This, or similar, boards can be integrated with most microprocessor-based system.
It is based on the SIM7600G cellular module from SimCom, which features high data rates and built-in GPS.
The advantage of using this type of module is their ease of integration - Linux drivers allow full Internet access and hence a wide range of data protocol options, including remote VPN access to the host device if required.
Sample LoRa board
The microprocessor features 32K of flash storage, digital and analogue IO, LiPo charging, and operates at very low power.
This type of board is ideal for connecting devices spread across a large site to a central gateway.
Customer case study//
IoT sensing for farming
Agri Samplers has developed automated scientific instruments that give farmers fast information about crop disease.
Part of an Innovate UK-funded program to research ways to reduce farm spraying, Walnut created a serverless IoT pipeline using Amazon AWS to process and analyse thousands of messages sent daily from the field.
A data analytics portal gives farmers real-time access to test results enabling them to make timely spraying decisions.