How do utilities decide which spectrum to use?
As they undergo digital transformation, utilities are investing in new technologies to modernize the grid and improve the existing grid’s security, reliability and resiliency. Access to a wireless network with superior coverage and adequate capacity is central to utilities’ security, reliability and independence needs. And spectrum is a fundamental building block. Utilities are likely new to the intricacies of spectrum. Our new case study explains why spectrum is important to the modernized grid and what considerations you must make when choosing spectrum for a utility’s specific needs.
Smart grids get smart about spectrum
Shared public consumer networks, subject to load-dependent reliability, don’t provide the security, reliability and independence required for providers of mission-critical services like utilities. That’s why utilities are adopting 3GPP technologies such as Private LTE (PLTE) as a primary communications technology for reliable and secure wireless networks.
Radio spectrum sets the parameters for a new, broad ecosystem of interconnected networks and devices based on PLTE that enables the application of telecommunications networks to new industries and novel use cases, including utilities.
“Like any wireless network, utility ICT systems need radio-frequency spectrum to function, and the reliability of the wireless communications may be affected by radio-frequency interference. Therefore, access to adequate and interference-free spectrum is a requirement if these networks are to work as intended.”
— Utilities Technology Council™ FCC filing, 2018
Highlights
How utilities use wireless networks
Wireless spectrum can be leveraged by utilities to facilitate the communication and coordination of many of their operations in a number of use cases including:
- Smart grid
- Distribution automation
- Advanced metering
- Reduction of opex
- Workforce connectivity
Choosing your flavor of spectrum
Spectrum can be categorized into three main categories:
- Low-band (450 MHz–1 GHz)
- Mid-band (1 GHz–6 GHz)
- High-band (24 GHz–71 GHz)
All three bands are applicable to utilities and can benefit the industry when setting up wireless infrastructure. Today, both low-band and mid-band are available to the industry . A utility’s choice of spectrum for the wireless networks would be based on their use cases.
Licensed or unlicensed
How critical is security and reliability to your use case? That will help the utility determine whether it needs licensed, unlicensed or shared spectrum.
Which bands are licensed, unlicensed and shared and what are the differences between them? Here’s what you need to know.
How much spectrum do you need? Factors to consider.
As with any wireless planning or deployment activity, a primary question is: How much spectrum is required? Two major aspects have to be considered to answer this question: Coverage and capacity.
Low-band spectrum provides increased coverage at the expense of speed/capacity.
Mid-band spectrum provides increased capacity due to larger channel bandwidths but has reduced coverage due to its propagation characteristics.
Low-band offers the most coverage but the least capacity.
The amount of spectrum needed is directly correlated with the total volume of traffic to be carried by a single wireless site.
How do utilities decide which spectrum to use?
To select the optimal band for your application, consider the capabilities of the spectrum and the capabilities you require for your use case. For instance, do you need wide coverage or focused capacity? Mission-critical or non-mission-critical security? This chart sums up the key factors to consider.
| Spectrum | Best suited for: | For applications requiring: | Amount of spectrum |
| Low-band | Smart grid sensor applications | Wide coverage, infrequent communication, and lower traffic volumes | 3+3 MHz / 5+5 MHz |
| Mid-band | Real-time communication traffic Higher volume video surveillance Drone traffic |
Focused capacity to supplement the coverage of low-band spectrum. Non-mission-critical traffic. | 10 MHz or higher, or shared spectrum such as CBRS |
| High-Band | Low-latency applications deployed in a specified footprint | Use cases that need a latency of <10 ms with focused coverage | 100 MHz or more of mmWave spectrum |
Calculating ROI: Why “MHz per pop” isn’t a good currency
When planning your wireless communication infrastructure, cost is a key component that can either hinder or promote the use for utilities, since fees can be a significant expense for utilities. Utilities might ordinarily use MHz per pop to calculate ROI. Higher population densities for a given region means faster ROI, leading to a higher MHz/pop measure. This model, however, does not map to spectrum leased or sold to utilities.
