Introduction to Millimeter Wave E-Band Technology

Millimeter Wave (MMW) technology, also known as E-band or V-band, is increasingly used for high-bandwidth applications, from enterprise data centres to individual smartphone users. While fibre optics remains the highest standard, MMW offers comparable bandwidth without the high costs or logistical challenges of fibre deployment.

Millimeter waves represent the RF signal spectrum in the 30-300 GHz range, with a wavelength of 1-10 millimetres. MMW is commonly used in the 38, 60, 70 and 80 GHz bands, making it a strong alternative for high-speed wireless communication.

Commercial Millimeter Wave (MMW) links from CableFree feature high performance, reliable, high capacity wireless networking with latest generation features.

MM Wave Spectrum

In the UK, there have been 3 frequency bands that have been allocated for commercial Millimeter Wave usage, these are as follows:

57 – 66GHz: The 60 GHz band (V-Band) is governed by OFCOM. The 57-64 GHz range is licensed and regulated, while 64-66 GHz is unlicensed and self-coordinated. The large amount of signal absorption via atmospheric oxygen and tight regulations make this frequency band more suited to short range, Point-to-Point and Point-to-Multipoint Millimetre Wave solutions.

71 – 76GHz and 81 – 86GHz: The 70GHz and 80GHz Millimeter Wave Bands (E-Bands) are governed by OFCOM for licensed operation only and are the most suited bands for Point-to-Point and Point-to-Multipoint, Millimeter Wave Wireless Networking and communication transmission. Each band offers a 5GHz spectral range which totals to be more than all other assigned frequency bands added together. Each 5GHz range can act as a single contiguous wireless transmission channel, allowing very efficient use of the whole band. In turn, these result in high throughput speeds from 1 to 3 Gbps whilst only using simple modulation techniques such as OOK (On-Off-Keying) or BPSK (Binary Phase Shift Keying). These throughput speeds are substantially higher than those found in lower frequencies using much more complex and advanced orders of modulation so even higher throughput speeds should be achieved with Millimetre Wave devices when utilising the same advanced techniques.

In the US, an additional band is available as well as the above which is:

92 – 95GHz: The 94GHz Millimeter Wave Band is governed by the Federal Communications Commission (FCC) Part 15 for unlicensed indoor use, and by FCC Part 101 for outdoor Point-to-Point applications. A 100 MHz range (94-94.1 GHz) is reserved for space-borne radios, reducing the spectral efficiency of the band, and limiting the transmission rate to under a few gigabits per second.

The band is available for use in a range of products and services. Highly directional “pencil-beam” signal characteristics permit different systems to operate close to one another without causing interference. Shorter wavelengths enable smaller, highly directive antennas, increasing user density and spectrum efficiency compared to lower frequencies, and allowing this spectrum to be used as a replacement for fibre optics. Unlike the 60 GHz band, the 71-76, 81-86, and 92-95 GHz bands are unaffected by oxygen absorption, improving range and reliability for outdoor applications. Some of the applications include:

• Point-to-Point Communications: High-speed wireless backhaul for telecom networks.

• Point-to-Multipoint Communications: Broadband Internet access and wireless local area networks (WLANs).

• Intersatellite Links: High-bandwidth communication between satellites.

• Radar Systems: High-resolution radar for automotive, security, and industrial applications.

• WirelessHD and IEEE 802.11ad: Ultra-fast wireless data transfer for consumer electronics and WiFi networks.

• Potential Fibre Optic Replacement: mmWave’s high capacity could supplement or replace fibre optics in certain scenarios.

Performance

Bandwidth & Scalable Capacity

Millimeter Wave technology offers significantly higher spectral bandwidth (5GHz available in each of the E-Band ranges), enabling speeds of 1.25Gbps Full Duplex up to 10Gbps. Unlike low frequency microwave signals, MMW uses narrow, focused beams allowing dense frequency reuse and up to 15x higher deployment density. This makes it ideal for high-capacity, interference-resistant Point-to-Point, Mesh, Ring and Hub & Spoke network topologies.

Propagation & Signal Attenuation

Millimeter Wave links can span up to 10km, but performance depends on equipment and environmental factors. Signal attenuation is primarily caused by moisture, especially rain at 70-80 GHz, while fog and humidity play smaller roles, only requiring considering for links at 5km+. Atmospheric oxygen is also a large factor in the 60 GHz range, but almost negligible in the other ranges, under 0.2 dB per km.

At the 70 to 80GHz bands, the rate of rainfall, measured in mm/hour, is the depending factor in signal loss. Signal propagation loss is also directly proportional to distance, so if the distance between transmitter and receiver is doubled, the loss in dB will be twice as much. Millimeter Wave performance is quite heavily dependent on rainfall and strongly affects availability (discussed below), however, successful links can even be set up in areas of occasional heavy downpours.

Availability

Millimeter Wave (MMW) wireless network reliability depends on factors like distance, link margin (transmit power, receiver sensitivity, beam divergence), and redundancy. While heavy rain can impact performance, sufficient link margin can prevent outages.

Availability is the key metric, representing the percentage of time a link is operational (e.g. 99.999% = ~5 hours downtime/year). ITU research provides expected link performance in global cities:

MMW offers strong inherent security due to its very narrow beamwidth (~0.36° with a 2 ft antenna) and low transmit power, making interception or detection difficult – ideal for secure communications.