More electronic systems are being adapted for use outdoors, for example information kiosks, but some high-temperature operation electronic systems, such as radios, need careful design considerations before they can operate effectively outdoors.
In these systems, fans are impractical, as they have a high failure rate, or mean time between failures (MTBF), in comparison to the electronic components. Servicing them incurs the cost of sending a repair truck, which is time consuming and could lead to unacceptable downtimes.
To avoid this, high-temperature outdoor units, such as radios, often use convection cooling.
Figure 1: A radio tower is a typical example of a high temperature operation outdoor electronic system. (Picture – Pixbay)
The demands of 5G
5G networks will be deployed to handle the increase in traffic data to connect devices in the Internet of Things (IoT). Fast upload and download speeds, with low latency will increase connectivity, for example in autonomous vehicle systems, as well as enhanced mobile broadband for home and enterprise use.
To increase data rates, the 5G architecture calls for a reduced distance between radios and user terminals, which causes a corresponding rise in the number of cell sites and nodes in the network. The rate of 'densification' of radio access networks (RANs) is considerable, with 10x more radios than 4G and 100x more than 3G networks, to meet 5G's Gbps data rate and low latency specifications.
In metropolitan areas, where there is a high concentration of users, cellular radios will become ubiquitous, but their design criteria remains strict. They must be compact as they will be mounted on telephone poles, lamp posts, the corners of buildings and curb-side municipal power supply cabinets. Locating 5G radios in these locations will subject them to a broad range of environmental conditions. The timing solution employed must have the capability to withstand high temperatures and maintain system functionality.