The 10 questions you need to ask
Whilst every situation will be different, here is a list of the 10 topics to address before choosing between a standard or proprietary protocol route:
- Network topology
How many members/nodes will participate in the wireless network and what is the interaction between them?
What is the required range between the transmitter and receiver? Is the distance fixed or will it vary?
- Data rate
What speed will the data need be transmitted at? Will it be low speed (e.g. infrequent messages), such as for monitoring and some control applications, or high speed, such as for video transfer? Lower messaging rates usually offer the best opportunity for long transmission range.
Is there a special need for low power consumption? If it is to be battery powered, consider battery size, life, recharging needs, replacement intervals and related costs. Is energy harvesting (e.g. solar power) a possibility?
- Common standards
Are there common standards that have to be met to interoperate with other part of the system?
What communications software protocols fit the application best? It’s important to find the best solution for the job and use well-tried standard solutions and open-source software.
What regulations need to be considered? Almost all wireless technologies require conformity to a standard. Some require licensing if using frequencies or if usage is outside of the license-exempt rules.
Do you need inbuilt security measures? Many wireless standards have security measures defined including encryption and authentication, and standard security methods can be used on top of proprietary communications solutions.
- Module-based or chip-based?
A further factor to consider is the benefit of choosing a module-based solution compared to a self-development based on a chipset. The benefits of selecting a module-based solution include a shorter time to market, ability to re-use its device certification (usually) and the device being a field-proven technology in terms of temperature, and antenna loads, for example. The disadvantages are possible increased unit cost and size, mass and shape limitations.