Building a point–to–multipoint radio network
is a significant investment for any organization
in terms of dedicated capital and human
resources. While some considerations might
be obvious – such as ensuring you understand
your current and future capacity requirements
– there is a number of less–obvious elements
that can influence the success of your project.
HERE ARE OUR TOP 10 FACTORS:
1. Invest in spectrum
Spectrum is likely to face greater congestion in years to
come. Unlicensed spectrum offers you no control over data
transmission priority or network availability, so investing in
licensed spectrum is the logical first step in protecting
Sub 1GHz channels offer greater propagation due to less
fading from weather impact and their ability to maximize
coverage. The wider antenna beamwidth in a sub 1GHz
channel means links can continue to operate even if an
antenna is offset due to wind or ground movement.
2. Bandwidth and IP performance
Data capacity is top of the list of features that determines
which network provider you choose. Understanding both
your current requirements and allowing for growth over
the life of the network is critical. However, capacity is not
just about bits per second — look for innovation around
compression rates, high order modulation, MIMO vs SISO,
and full duplex vs half duplex to ensure your investment
in spectrum is optimized.
So investing at the outset in radios that can co–exist with
other equipment is important.
6. Quality of Service
Mission–critical transmissions must be granted priority;
bandwidth must not be used to transmit non–essential
data when network equipment is in an alarm state. To avoid
this, you must either invest in a switch to mark IP traffic, or
select radios that can set the Quality of Service (QoS) via
configurable filters or rules.
In many countries, Critical Infrastructure Protection is a
key issue, so you need to look for security features such as:
› Ethernet and serial ports isolation,
› Over-the-air encryption,
› Sticky MAC (or persistent MAC learning) where devices
connecting to the Ethernet can be blocked based on
their MAC addresses,
› Radius Server Support for authentication of users.
Three key factors impact system reliability and should be
› Quality engineering is the starting point for maintaining
reliability — look for manufacturing facilities that meet
› Built-in redundancy at base stations with a 1–plus– 1
approach ensures you stay live even if a radio goes down.
IP provides permanent connectivity where responses are
immediate, but traditional SCADA point–to–multipoint
systems don’t operate that way. IP traffic can be
bandwidth–hungry, so excellent IP performance is important
for future–proofed point–to–multipoint networks. Key
elements of IP performance are high data rates, low latency
and full duplex communications.
Low latency is vital for mission–critical infrastructure.
The sooner you are aware of issues in outlying areas, the
better the outcomes for your business and your customers.
Industry recommendations put latency below 100ms, but
you can potentially achieve latency rates of 30ms or even
better, with smart network design and clever technology
incorporated into your chosen radios.
4. Network integration supporting
Existing RTUs may use serial data from multiple protocols
and standards. To support migration from a legacy system
to an IP–based system, your radios will need both IP and
serial interfaces that support a range of protocols.
5. High tolerance to interference
Particularly important at busy sites such as where radios
are co–located with cellular services, radios must be highly
tolerant to interference. Features such as bandpass filters
to clean noise, and a wide dynamic range can go a long way
to minimizing interference.
As more radios are installed adjacent to your original
installations, you can expect increasing noise that could