The Ultimate Guide to CBRS for WISPs

First, let’s define what CBRS is. CBRS is Citizens Broadband Radio Service, and it refers to the service that allows wireless providers to operate in the 3.5 GHz to 3.7 GHz frequency band. In the past, this frequency was only reserved for satellite ground stations and the US military. Some WISPs were also operating on this band without a license.

Now, the Federal Communications Commission (FCC) has made this spectrum available to wireless providers on a shared, prioritized basis. Spectrum availability is divided by tiers to ensure that priority users have uninterrupted access. However, even those on the lowest tier will still have reliable service because the spectrum is constantly monitored and allocated.

Tiers

The FCC has prioritized the spectrum according to these three tiers.

Tier 1

Tier 1 is reserved for incumbents. The incumbents in the 3.5 GHz band are the US Navy, satellite ground stations, and grandfathered-in fixed wireless providers operating under Part 90 rules. Some grandfathered fixed wireless providers have until 2023 to make the transition to CBRS rules. The Navy must take first priority in case of any emergency communications. Satellites also receive crucial, sensitive information and must be enabled to operate without interruption.

Tier 2

Tier 2 is for Priority Access License (PAL) holders. The FCC auctioned seventy megahertz of spectrum with seven licenses available per county. Ninety-one percent of the 22,631 licenses were sold at the auction in August 2020. Some who purchased these licenses may resell them in the secondary market or share them under GAA.

Tier 3

Tier 3 is General Authorized Access (GAA). This spectrum is available to any WISP who registers with a Spectrum Access System (SAS). WISPs operating under GAA can use any unoccupied spectrum on the band but must yield priority to higher tiers. The SAS provider is responsible for managing and allocating the spectrum to ensure that it’s adequately shared, and priority is given without causing unnecessary interference.

Regulations, Costs and Funding

If you want to use CBRS under GAA, you’re probably wondering what the regulations and costs are to operate. Everyone under GAA has to follow the same regulations and pay certain costs per user, which vary depending on the SAS that you choose.

Most Part 90 licenses are now expired. To meet the new Part 96 regulations, you’ll need to investigate whether you need a software upgrade and possibly an equipment upgrade. We’ll go into more detail about that later. You’ll also need to get a Certified Professional Installer (CPI) certification to ensure that you understand your responsibilities and best practices for operating as a WISP under CBRS.

Equipment and software upgrades, certification costs, plus the extra cost per device per month may seem like a large investment at first. However, with wider coverage and better service, it will be worth it in the long run. If you don’t have the funds available to get started, there are grants and subsidies available to help WISPs provide coverage in underserved areas.

Here are a few programs you might consider:

• The IMLS CARES Act grants provide some funding to WISPs serving libraries and other educational institutions.
• The USDA ReConnect program offers funding for businesses that provide high-speed internet access to rural areas.
• The Community Connect Grant focuses on community-oriented connectivity, such as providing better access to education and health care through internet access. It’s a yearly competition.
• The Telecommunications Loan and Loan Guarantee Program offers loan opportunities year-round to WISPs serving rural or underserved communities.

Is it really worth it to make the investment in CBRS, or will you end up facing the same problems? There are some proven reasons why CBRS greatly improves your service offerings, keeping your current customers satisfied and attracting more customers.

Give Customers Higher Speeds at an Affordable Price

With online learning and working from home, your customers require high speeds more than ever before. For just a few dollars more per month, you can dramatically increase their speeds. Most CBRS systems are based on small-cell LTE technology, which allows customers to get speeds ranging from 100 Mbps to 1 Gbps.

CBRS is much cheaper than fiber and can reach the needs of day-to-day customers.

Extend Your Service’s Reach

If you’ve been operating on a different frequency, your bandwidth may be limited. As you attempt to add volume of customers, you won’t be able to keep providing the same level of service. With greater bandwidth available on CBRS, you can add more customers and maintain a high level of service.

If you’re operating on an ISM band with IEEE 802.11, some of your customers may experience poor service if they live in a heavily wooded area. With LTE, signals can penetrate through dense foliage and other obstacles so Non-Line-of-Sight (NLOS) performance greatly improves.

Reduction of Interference/Outages

Nothing is worse for customer experience than sudden interference or outages when they’re attempting to work or study. When you’re operating on unlicensed spectrum, it’s difficult to control interference. No one is consistently managing it, and if there’s heavy usage from different sources, interference and outages inevitably occur.

With CBRS, spectrum is managed by a SAS vendor, who minimizes interference by using an environmental sensing capability network (ESC). The ESC lets them know when incumbents will need to use the system so that they can quickly redistribute the spectrum and avoid outages.

If you’d like to take advantage of CBRS to improve your service offerings, you’ll need to analyze spectrum availability, evaluate whether you need a hardware upgrade, and choose a SAS provider. We’ll walk you through the steps in detail.

Step 1

Analyze the Spectrum Available in Your Area

The first step before you commit to using CBRS is to analyze the spectrum available in your area to make sure you’re eligible. If you’ve already been operating as a WISP, you may already be aware of the availability.

If not, you can use a spectrum analysis tool to find out how many WISPs are in the area and ensure there’s enough capacity. Some SAS providers offer assistance with spectrum analysis.

Step 2

Upgrading Your Hardware to Use CBRS

For you and your customers to reap the benefits of CBRS, you’ll need to make a few upgrades. If you’ve already been operating on the CBRS band under Part 90, the transition will require fewer steps than if you’re on a different band. We’ll show you what you need to do whether you’re migrating to Part 96 or starting a new CBRS deployment.

Migrations

If you’re migrating from Part 90 to Part 96, the first step is to check your Citizens Band Radio Service Device (CBSD) equipment and see if it already complies with Part 96 rules. This includes security requirements, geo-location and reporting capabilities, frequency reporting capabilities, and power limits. Refer to the government documentation for all the specifications. If your device is compliant, there’s no need for an equipment upgrade. All you’ll need is a software upgrade.

If an upgrade is necessary, follow the same steps as new deployments. And if you’d like some more advice on migration, check out our Roadmap to Part 96 Migration.

New Deployments

For new deployments, you most likely do need to purchase new equipment. An exception is if you’ve been using the Cambium PMP 450m on ISM bands. That’s compatible both on the ISM bands and on CBRS.

If you do need new equipment, there are 24 OEMs currently producing compliant devices. With this number of options, there’s a good chance that a brand you trust is already producing one of them. However, if you need assistance choosing a device, some SAS providers can help you by making some recommendations.

To deploy your LTE network, you’ll need to install your CBSDs to form a Radio Access Network (RAN). If you have an existing network, you can replace your devices on the same towers.

After that, you’ll need to install an Evolved Packet Core (EPC) device. The EPC can be cloud-based, or located at the same place as the CBSDs. This allows packet transmission among the CBSDs, on the local network and on connected networks. It’s made to operate on a 4G network but can also be expanded to include 5G.

Step 3

Choosing a SAS Provider

After verifying your equipment is compliant, the next step is to choose a SAS provider. But what exactly is a SAS, and what is a provider supposed to do for your business?

What is SAS?

SAS refers to Spectrum Access System, a cloud-based service that manages the wireless communications of devices transmitting in the CBRS band. It ensures that priority is given according to tiers: first to the incumbents, then to PAL, then to GAA. The current providers are Federated Wireless, Google, CommScope, Key Bridge, AmDocs, and Sony.

Anyone who wants to use CBRS now has to sign up with a SAS provider. It doesn’t matter if you missed out on the PAL auction. Once you register with a SAS, you’ll be assigned spectrum under GAA.

Even though you’re in the third tier, it’s the responsibility of the SAS provider to minimize interference as much as possible by using ESCs, tracking usage, and coordinating with other SAS providers.

What You Should Expect from a Good SAS Provider

It may be more difficult to choose a SAS provider than an OEM. You’re probably already familiar with many of the manufacturers and equipment features. But what are the distinctions between SAS providers? You can’t physically see the product they’re offering. Is one really better at preventing interference than the others? Here are a few important qualities that a good SAS provider should have.

1. Spectrum Lifecycle Management
   A good SAS provider can offer solutions beyond monitoring your spectrum. Look for a SAS that offers additional services such as analyzing spectrum availability at the beginning, CPI certification, and RAN set-up assistance.
2. Prevents Interference Using a Comprehensive ESC Network
   Not all SAS providers have a nationwide, triple-redundant, registered ESC network. If the SAS’s ESC network is lacking, it won’t be as effective in predicting when incumbents will need to use the spectrum, and you might experience interference or outages. A triple-redundant system ensures 99.999% spectrum availability, even if unexpected events require the incumbents to use more of it. Make sure that your provider’s network is sufficient.
3. Provides 24/7 Customer Service
   If you start experiencing interference, you want to be able to report it and have the SAS provider identify and address the cause of it right away. When choosing a provider, find out how you can reach them with any issues and how quickly they’ll respond. Your own customers expect you to respond quickly to requests, so you shouldn’t expect anything less from a SAS provider.
4. Protects Your Privacy
   When you sign up with a SAS provider, you need to give them your location and customer information. Make sure that they’ll keep that information private and won’t share it with other WISPs or use it themselves. Don’t choose a SAS that’s also an internet service provider. They might not share your information with others, but they could use it themselves to compete against you.

Other Qualities to Consider:

• FCC certified
• Open, neutral partner ecosystem to help you liaise with vendors
• Highly experienced team for complex connectivity deployments and service improvements
• Experienced with delivering low-cost, high-speed network for critical infrastructure industries and remote areas