ISM radio technology

The WNC products are implemented using the latest in low-power radio technology, enabling the nodes to be battery powered. Battery life can be as long as 10 years. The radio nodes operate in the license free ISM (Industrial, Scientific, Medical) bands at 433MHz, 868 MHz or 915 MHz and use FHSS (Frequency Hopping Spread Spectrum ) technology to enable a robust radio link. The range (in line of sight) can be more than 1000 meters for low power solutions and up to 5 km for nodes equipped with extra power amplifiers. To extend radio coverage, additional radio repeaters can be installed.

In the recent years the development of wireless integrated circuits (RFIC) has made large progress with respect to reliability, size, cost and power consumption.

In combination with intelligent communication protocols, these technology improvements enable small size, cost efficient wireless communication systems that are reliable even in hostile industrial conditions.

ISM protocols and applications

Since the wireless technology became more accessible a few years ago, there has been a development of different standards and solutions depending on the end product application. The figure below summarizes how the different protocol standards address different needs/applications.

When choosing the appropriate radio technology, the following characteristics must be taken into consideration:

  • Radio communication reliability and range
  • Power consumption
  • Data rate / throughput
  • Cost
  • HW size
  • Network complexity
  • Interoperability

Each of the differentiators are interfering with each other (for example, increasing the data rate will by nature decrease the maximum range of the radio solution or demand higher power consumption).

For wireless monitoring systems of industrial processes, the most important criteria are communication reliability/range and power consumption.

To obtain long range solutions at low power consumption, the optimum radio technology will run at moderate data rate (250kbit/s and below) and with proprietary radio protocols.


The size of radio transceivers has become very small in the recent years. The CC2500 transceiver from Texas Instruments (ex. Chipcon) is 4x4mm (source: www.ti.com)

ISM radio network structure

Simple one-way point to point connections are the easiest to implement, but has limitations with respect to liability and range. On the other side of the scale, we have a 2-way meshed networks, which will give a robust and long range network, however at the cost of complex network protocols that demand high processor capacity and long development and maintenance.

                 Meshed networks is a means to obtain range and robustness

To get a short description of the ISM radio protocol implemented by WNC, click here...