Peraso mmWave Technology: Serving Affordable Gigabit Wireless Infrastructure To Dense Urban Environments

Broadband Infrastructure Challenges in Informal Settlements

Travel to any major city around the world and you’ll likely have access to broadband internet. However, a large segment of the global population is living in densely populated, informal urban settlements where unfortunately, the internet is not always available or reliable.

Figure 1. Dense Neighborhoods Lack Conventional Network Infrastructure

The most important determination of the success of any broadband service lies in the quality of its distribution infrastructure. The common choices for last-mile technologies are optical fiber, or copper cable (DSL), and coax (DOCSIS). However, in informal settlements, installation of this media is not feasible due to issues related to poor civic infrastructure, unstable power grids, and vandalism.

Alternatively, there are wireless options for last-mile infrastructure, including 4G/5G normally provided by carriers. In the case of 4G/5G technology, the infrastructure available in informal settlements, particularly the electrical power infrastructure, is not able to support highly sophisticated base stations. What’s more, the average income levels in these settlements do not support the installation costs or carrier data charges creating a negative ROI for providers. 

For all of its success, Wi-Fi as an access medium has also been its Achilles heel for network infrastructure. The problem of congestion and interference in the 2.4 and 5.8 GHz Wi-Fi bands is well known. WISP operators the world over can document the problems that occur when many uncoordinated Wi-Fi BSS domains are contending for the same spectrum resources.  

The pressure on the allocated Wi-Fi spectrum has led to the recent release of a new spectrum in the 6 GHz band, but this is only accessible to the latest and most expensive Wi-Fi 6E/7 hardware. To leverage the billions of devices that are in use today with legacy spectrum usage, it is clear that utilization of the 6 GHz spectrum does not resolve the problems of congestion and interference.

60 GHz mmWave Well Suited for Informal Settlement Broadband Infrastructure

The solution? Fortunately, in nearly every country, the 60 GHz license-free band is available.  There has been significant evolution in the available phased array antenna and dish technology and positive amendments to regulatory requirements now enable 60 GHz spectrum to fill the role as a reliable, cost-effective, and high bandwidth infrastructure technology.

Figure 2. 2-60 GHz Distribution for Reliable Network

Utilizing a 60 GHz wireless backbone provides operators with several advantages in dense informal settlements. They include:

• License-free spectrum, thus providing an economic model that allows for extremely low-cost service
• 60 GHz RF signals that are tightly controlled with advanced beam-forming techniques and thus support the highly dense footprint presented in informal settlements
• The 60 GHz frequency band does not interfere with the 2.4 and 5 GHz Wi-Fi
• 60 GHz utilizes the IEEE 802.11ad protocol, which enables very cost-effective hardware for the broadband infrastructure
• Easy to deploy, low SWAP (Size, Weight, and Power) hardware enabling solar/battery operation in intermittent power conditions
• The protocol has extremely low latency

It is for these reasons that WISPs around the world are now implementing 60 GHz as the first choice for infrastructure solutions. In the last few years, significant changes have been made by the FCC regarding 60 GHz operation. Other countries including many in the EU and in Africa have also adopted some of these modifications which include: 

• Allowances in the EIRP limitations that enable up to 80 dBm average when utilizing a high gain antenna such as a dish or lens
  1. Additional antennae gain greatly enhances link margins while also naturally narrowing the main antenna beamwidth and reducing side lobes
  2. This is ideal for dense deployments where co-location of several Access Points may be necessary
• Some countries have expanded the available spectrum up to 71 GHz paving the way for additional operating channels which are outside of the oxygen absorption spike that continues to plague the lower channels (57-64 GHz)

The net-net is that digital connectivity is available to the masses thanks to low-cost equipment that is now able to support ranges up to 8km for point-to-multipoint operation and 20+ kilometers for point-to-point.  

To further improve the flexibility and link margin of the 60 GHz products, reduced channel bandwidths are now offered. Utilizing ½ (1 GHz) or ¼ (500 MHz) wide channels, the operator has more channel options with improved range performance. 

60 GHz mmWave Plus Wi-Fi Enables a Billion Users

While it’s clear that 60 GHz is an ideal choice for informal settlement infrastructure, there’s a last step in the pipeline that is required to get user devices actually connected. Enter Wi-Fi technology. Proven to be the most affordable and ubiquitous technology to provide digital connectivity, Wi-Fi is available in every mobile device today. What’s more, the rollout of pre-paid plans enables very low-cost service and is often times significantly more flexible and affordable than the major Mobile Network Operator services we are all familiar with.

It’s the dawn of a new technology era and networks are only getting more congested by the day. It is time for operators and equipment vendors to re-examine what’s possible and look for ways to solve tomorrow’s connectivity issues today with proven license-free 60 GHz network solutions that have proven more than capable of bringing the internet to the masses. 

Peraso Is The World’s Leading Supplier Of 60 GHz Technology

Peraso, as the vendor of core chipsets and modules, has been working with our customers and WISPs to create solutions that leverage the cost advantages of license-free spectrum with our field-proven hardware to create a new class of products that meet the challenges of dense network deployments.

Figure 3. Peraso Modules Simplify and Cost-Reduce HW

Thanks to Peraso’s innovative solutions, a point-to-multipoint 60 GHz network can provide a backbone for Wi-Fi hotspots. Peraso has also successfully demonstrated that multi-gigabit, bi-directional throughput, and low latencies, as well as the lack of interference, provide a robust and high-performance network.

The system is easily scalable. Dedicated 60 GHz point-to-point links can be utilized to extend the reach of the backbone without fear of interference due to the tight antenna beam pattern available with mmWave RF system.

About the Author

Ronald Glibbery is co-founder and CEO of Peraso, leading all functional areas of the company. Prior to Peraso, he held executive positions at Kleer Semiconductor, a fabless semiconductor company focused on wireless audio technology, and Intellon, a pioneer and leader in the development of semiconductor devices used for powerline communications. He has held other executive roles at Cogency Semiconductor, LSI Logic Canada, Inc., and LSI Logic Corporation. Glibbery holds a B.E.Sc. in Electrical and Electronics Engineering from the University of Western Ontario.