The IP 400 project has been referred to as ‘the Packet Radio of the 21st Century’, which is the primary vision, and the motivation is to bring a higher speed data mode to the 400MHz band that will create a data transport for modern-day data streams from digital radios such as DMR, D-Star, P25 and M17 to name a few.

The starting point is to use off the shelf devices, designed for commercial use, which are capable of transmitting in the 400 MHz band. Around these a simple node has been created that can send and receive a data frame using 4FSK at speeds from 100 up to 200Kilo bits/second, in 100KHz bandwidth. This is fast enough for most data traffic, and will be known as the ‘primary mode’ of transmission. To live within the restrictions placed on data rates by some countries, the 100Kb/s mode will be used for initial contacts.

Primary Mode

The goal of the primary mode is to be able to establish a local mesh network and routing information. There are two components, hardware and software. The hardware is built around an STM32WL33 processor, which is a 400MHz transceiver around and ARM Cortex processor. This is realized as a Pi HAT in the Pi Zero form factor, and contains firmware to create a local mesh network, and send and receive frames in the 802.15.4 format. This hardware is known as the ‘mini node’.

The mesh network is built by periodically sending a ‘beacon’ frame periodically, which has data about the node such as its callsign, IP address, and location information. The location data can be static or derived from an attached GPS receiver.

The name was chose to represent an ‘Intelligent Protocol’, which can dynamically change formats and data rates as needed.

Secondary Mode

The plans for the secondary mode are to widen the bandwidth to 2.56MHz and introduce a series of OFDM carriers which will ‘wrap’ the primary mode carrier and increase the data rate to 1Mb/s and beyond. This will provide ample bandwidth for compressed digital video.

The use of OFDM not only increases the data rates, but also opens up the possibility of multiplexing data traffic to more than one node simultaneously. There are 230 data carriers planned, so theoretically as many nodes could receive data simultaneously. In practice that will probably not be the case, as the number of carriers required will be determined by the data bandwidth for a specific application. A diagram of the occupied bandwidth is below.

Software

All software generated by the project is open source, it can be found on the primary GitHub repository, a link to it can be found on the Links page. It is our goal to ensure that this remains open to encourage experimentation and development activities in the amateur community. Please join the developer group if you have something that you would like to contribute.

Hardware

The Alberta societies act, which is our governing legislation, prohibits the society from engaging in any kind of trade activities. This presents a problem with the hardware, which has to be designed, manufactured and distributed to interested parties. As we cannot do this directly, we have engaged commercial partners who will look after that aspect of the project for us, and have the requisite expertise. If you place an order on this site, it is forwarded to a partner for fulfillment. Revenue generated by commercial partners is donated back to the society.

Having a common hardware platform is paramount to the success of the project, and also enables us to provide support, as debugging software on a common platform is a relatively straightforward exercise. We do not have the time or resources to debug or support our software on hardware generated by others, not to mention that building hardware is also a complex and expensive proposition, involving knowledge in circuit design, PCB layout and manufacturing. We are leaving that to the professionals.

As the project progresses, the PCB component will become more complex and required specialized equipment to manufacture. Establishing these relationships now will ensure our continued success. After all, where did you get the rig you have now?