Gigabit Wireless Links using V-Band 60GHz Millimeter Wave MMW Technology
So-called “V-Band” refers to high frequency microwave signals in the Millimeter Wave radio bands which enable high capacity wireless communications. The band is useful for moderate distances up to around 1km with clear “line of sight”, and for short-range mobile devices. In many countries, V-band is “Unlicensed” (license free) which encourages widespread use.
What is 60GHz V-band technology?
The V band (“vee-band”) is a standard designation by the Institute of Electrical and Electronic Engineers (IEEE) for a band of frequencies in the microwave portion of the electromagnetic spectrum ranging from 40 to 75 gigahertz (GHz).The V band is not heavily used, except for millimeter wave radar research and other kinds of scientific research. It should not be confused with the 600–1000 MHz range of Band-V (band-five) of the UHF frequency range.
The V band is also used for high capacity terrestrial millimeter wave communications systems. In the United States, the Federal Communications Commission has allocated the frequency band from 57 to 71 GHz for unlicensed wireless systems. These systems are primarily used for high capacity, short distance (less than 1 mile) communications. In addition, frequencies at 70, 80, and 90 GHz have been allocated as “lightly licensed” bands for multi-gigabit wireless communications. All communications links in the V band require unobstructed line of sight between the transmit and receive point, and rain fade must be taken into account when performing link budget analysis.
Applications for 60GHz V-band
Very short range Wi-Fi
The Wi-Fi standard IEEE 802.11ad utilizes the 60 GHz (EHF microwave) spectrum with data transfer rates of up to 7 Gbit/s for very short ranges of up to 10 metres (33 ft). Also the newer IEEE 802.11ay uses the same band. Where 802.11ad uses a maximum of 2.16 GHz bandwidth, 802.11ay bonds four of those channels together for a maximum bandwidth of 8.64 GHz. MIMO is also added with a maximum of 4 streams. The link-rate per stream is 44Gbit/s, with four streams this goes up to 176Gbit/s. Higher order modulation is also added, probably up to 256-QAM.
As mobile operators need more and more bandwidth, they are turning to new frequency bands to lower their wireless backhaul costs. Both license-exempt V band spectrum (57-71 GHz) and E band spectrum (71-76 GHz, 81-86 GHz and 92-95 GHz) have clear technological and economic advantages. The 27 GHz allocated in these bands allows multi-Gigabit per second capacities far exceeding the 6-38 GHz bandwidth-limited frequencies.
In the V band and E band spectrum, wireless systems can utilize the significantly larger allocated spectrum and channels to deliver multi-Gigabit data rates. This enables a simple, robust, and low cost modem and radio design. Thus, V-Band and E-Band, millimeter-wave wireless systems provide significant cost advantages over 6-38 GHz wireless systems – allowing scaling capacity to Gigabit capacities, without additional radio equipment and licensing fees.
Internet service providers are looking for ways to expand gigabit high-speed services to their customers. These can be achieved through fiber to the premises broadband network architecture, or a more affordable alternative using fixed wireless in the last mile in combination with the fiber networks in the middle mile in order to reduce the costs of trenching fiber optic cables to the users. In the United States, V band is unlicensed. This makes V band an appealing choice to be used as fixed wireless access for gigabit services to connect to homes and businesses.
As of March 2017, several US companies—Boeing, SpaceX, OneWeb, Telesat, O3b Networks and Theia Holdings—have each filed with the US regulatory authorities “plans to field constellations of V-band satellites in non-geosynchronous orbits to provide communications services,” an electromagnetic spectrum that had not previously been “heavily employed for commercial communications services.”
V-Band Regulations and Licensing
In many countries, V-band is “Unlicensed” (license free) which encourages widespread use. A few countries retain 60GHz for licensed or defence applications. The specific frequencies which are allowed to be used can vary between different countries.
CableFree 10Gbps MMW links have been installed for Safe City applications
Using the latest 10Gbps Millimeter Wave wireless technology, the links connect Safe City customer sites with a full 10Gbps (10Gig-E) full duplex capacity, with no compression or slow-down.
CableFree has pioneered high speed 10 Gigabit Millimeter Wave (MMW) technology to connect sites where fibre optics are unavailable, too slow to provision, too expensive or at risk of damage. In busy cities, fibre optics is usually installed in ducts underground which are prone to disruption when digging or building works take place.
This client had already installed fibre optics for major CCTV backbones around the city. However, 3rd party building works disrupted the ducts severing the fibres, causing major outage in the network and loss of CCTV coverage – putting citizens at risk.
CableFree 10Gbps Millimeter Wave links offer an ideal alternative to fragile fibre optics: the radio units are installed on sites owned by the customer, bringing the full network under user control and management. The units are typically mounted on building rooftops well away from street-level disruption, which are easy to access, secure and defend. MMW wireless links can be installed in hours, not weeks, and at a tiny fraction of the cost of trenches and ducts for fibre optics.
Reliable operating distances of 5-8km depending on climatic region are ideal for city-scale networks. A full range of planning tools allows users to predict performance prior to purchase or installation. The E-band (70-80GHz) frequencies are available in many countries with “light license” and are uncongested, with narrow “pencil beams” allowing dense re-use of the spectrum with no interference between links or users. The narrow beams make such link are inherently secure, with proprietary signals and encoding.
For long links, the Adaptive Coding and Modulation feature enables the MMW link to dynamically adjust modulation in high rainfall conditions to ensure link uptime, capacity and range are maximised. For shorter links and long links in low rainfall regions, the links retain 10Gbps at all times.
10Gbps MMW links are a movable asset: if the network requirements change, or different sites require connecting, the links can be moved to the new sites immediately, retaining all the investment in infrastructure. For Special Events and Disaster Recovery, temporary links can be deployed using generator or alternative “off grid” (Solar + Battery) power if no AC power is available on sites. The units can be mounted on tripods or stationary vehicles as required for rapid deployment.
For mobile operators, advanced features such as IEEE 1588v2, SyncE and management are included which make CableFree MMW ideal for RAN backhaul for 4G & 5G networks. CableFree 10Gbps MMW is upgradable to 20Gbps and 40Gbps with “stacking” giving the very highest throughput in the wireless industry, comparable to fibre optic backbone networks.
For more information please visit the CableFree website or contact our expert team:
Comparison between 8, 16, 32, 64, 128, and 256 QAM types of Quadrature Amplitude Modulation
Gigabit Wireless Networks commonly use QAM modulation to achieve high data rate transmission. So what is QAM?
Introducing Quadrature Amplitude Modulation
QAM, Quadrature amplitude modulation is widely used in many digital data radio communications and data communications applications. A variety of forms of QAM are available and some of the more common forms include 16 , 32 , 64 , 128 and 256 QAM. Here the figures refer to the number of points on the constellation, i.e. the number of distinct states that can exist.
The various flavours of QAM may be used when data-rates beyond those offered by 8-PSK are required by a radio communications system. This is because QAM achieves a greater distance between adjacent points in the I-Q plane by distributing the points more evenly. And in this way the points on the constellation are more distinct and data errors are reduced. While it is possible to transmit more bits per symbol, if the energy of the constellation is to remain the same, the points on the constellation must be closer together and the transmission becomes more susceptible to noise. This results in a higher bit error rate than for the lower order QAM variants. In this way there is a balance between obtaining the higher data rates and maintaining an acceptable bit error rate for any radio communications system.
QAM is in many radio communications and data delivery applications. However some specific variants of QAM are used in some specific applications and standards.
For domestic broadcast applications for example, 64 and 256 QAM are often used in digital cable television and cable modem applications. In the UK, 16 and 64 QAM are currently used for digital terrestrial television using DVB – Digital Video Broadcasting. In the US, 64 and 256 QAM are the mandated modulation schemes for digital cable as standardised by the SCTE in the standard ANSI/SCTE 07 2000.
In addition to this, variants of QAM are also used for many wireless and cellular technology applications.
The constellation diagrams show the different positions for the states within different forms of QAM, quadrature amplitude modulation. As the order of the modulation increases, so does the number of points on the QAM constellation diagram.
The diagrams below show constellation diagrams for a variety of formats of modulation:
Bits per symbol
The advantage of using QAM is that it is a higher order form of modulation and as a result it is able to carry more bits of information per symbol. By selecting a higher order format, the data rate of a link can be increased.
The table below gives a summary of the bit rates of different forms of QAM and PSK.
BITS PER SYMBOL
1 x bit rate
1/2 bit rate
1/3 bit rate
1/4 bit rate
1/5 bit rate
1/6 bit rate
QAM noise margin
While higher order modulation rates are able to offer much faster data rates and higher levels of spectral efficiency for the radio communications system, this comes at a price. The higher order modulation schemes are considerably less resilient to noise and interference.
As a result of this, many radio communications systems now use dynamic adaptive modulation techniques. They sense the channel conditions and adapt the modulation scheme to obtain the highest data rate for the given conditions. As signal to noise ratios decrease errors will increase along with re-sends of the data, thereby slowing throughput. By reverting to a lower order modulation scheme the link can be made more reliable with fewer data errors and re-sends.
On Dec. 16 2013, Ofcom—the UK telecom regulator—announced a new approach for the use of E-band wireless communications in the United Kingdom.
To summarize, the new approach, which is available for licensing after Dec. 17, 2013, splits the band into two segments. Ofcom will coordinate the lower segment of 2GHz, while the upper segment of 2.5GHz will remain self-coordinated as per the prior policy.
The segment Ofcom coordinates will follow the usual regulatory processes for all the other fixed link bands it oversees. Moreover, OFCOM has already updated all the relevant documents and forms to accommodate E-band. While wireless vendors would have preferred the larger portion of spectrum to have been granted to the Ofcom-coordinated process, we welcome this new arrangement because it provides an option for greater security and peace of mind to operators in terms of protection from interference than was envisaged for the previous all self-coordinated spectrum regime.
Latest E-Band regulation by OFCOM
For a more detailed look at the new E-band arrangement, Figure 1 shows the Ofcom-coordinated section sitting in the lower half of both the 71-76GHz and 81-86GHz bands thus allowing for the deployment of FDD systems in line with ECC/REC(05)07.
Figure 1: Segmented Plan for Mixed Management Approach (click on figures to enlarge)
In terms of channelization within the Ofcom-coordinated block, the regulator announced that it would permit 8 x 250MHz channels, 4 x 500MHz channels, 1 x 750MHz channel and 1 x 1000MHz channel as per ECC/REC(05)07. Ofcom also stated that 62.5MHz and 125MHz channels will be implemented as soon as the relevant technical standards, etc., from ETSI are published. Figure 2 shows the Ofcom channel plan:
Figure 2: Ofcom Permitted E-band Channelizations
Regarding equipment requirements, Ofcom stated that it will allow equipment that meets the appropriate sections of EN 302 217-2-2 and EN 302 217-4-2. This includes the antenna classes (e.g., classes 2-4) that will allow the deployment of solutions with flat panel antennas. We welcome this approach and hopes that other regulators—notably the FCC in terms of antenna requirements—currently considering opening up and/or revising their rules for E-band adopt similar approaches.
The license fees for the self-coordinated segment remains at £50 per link per annum, whereas in the Ofcom-coordinated segment the fees are bandwidth based as reflected in Figure 3:
Notwithstanding the current fees consultation process that Ofcom is undertaking, these “interim fees” will remain in place for five years, after which time the results of the fees review may mean that they will be amended.
Figure 3: Ofcom Bandwidth-based Fees
Also because of responses received during the consultation process, within the self-coordinated block, Ofcom will now require the following additional information for the self-coordination database: antenna polarization (horizontal, vertical or dual), ETSI Spectrum Efficiency Class and whether the link is TDD or FDD.
Millimeter Wave, also know as MMW or Millimetre Wave technology is being rapidly adopted for users ranging from enterprise level data centres to single consumers with smart phones requiring higher bandwidth, the demand for newer technologies to deliver these higher data transmission rates is bigger than ever before.
A wide range of technologies exist for the delivery of high throughput, with fibre optic cable considered to be the highest standard. However, fibre optics is not unmatched, especially when all considering economic factors. Millimeter wave wireless technology offers the potential to deliver bandwidth comparable to that of fibre optics but without the logistical and financial drawbacks of the deployments.
Millimeter waves represent the RF Signal spectrum between the frequencies of 30GHz and 300GHz with a wavelength between 1 – 10 millimetres but in terms of wireless networking and communications equipment, the name Millimeter Wave generally corresponds to a few select bands of radio frequencies found around 38, 60 and, more recently, the high potential 70 and 80 GHz bands that have been assigned for the public domain for the purpose of wireless networking and communications.
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 60GHz Millimeter Wave Band or V-Band is governed by OFCOM for licensed operation. 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. Between 57 – 64GHz the band is licensed and regulated but from 64 – 66GHz the band is unlicensed and self coordinated.
71 – 76GHz and 81 – 86GHz: The 70GHz and 80GHz Millimeter Wave Bands or E-Bands are governed by OFCOM for licensed operation only and are regarded to be the most suited band for Point-to-Point and Point-to-Multipoint, Millimeter Wave Wireless Networking and communication transmission. Each band has a 5GHz spectral range available 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 and 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. It should be only a matter time before market demand brings these to the forefront.
In the US, an additional band is available as well as the above which is:
92 – 95GHz: The 94GHz Millimeter Wave Band or W-Band is governed by the FCC Part 15 for unlicensed operation also but only for indoor usage. It may also be used to outdoor Point-to-Point applications following the FCC Part 101 regulations but due to a range between 94 – 94.1GHz being excluded, the band is less spectrally efficient than the others.
The 71-76, 81-86 and 92-95 GHz bands are also used for point-to-point high-bandwidth communication links. These frequencies, as opposed to the 60 GHz frequency, do not suffer from the effects of oxygen absorption, but require a transmitting license in the US from the Federal Communications Commission (FCC). There are plans for 10 Gbit/s links using these frequencies as well. In the case of the 92–95 GHz band, a small 100 MHz range has been reserved for space-borne radios, making this reserved range limited to a transmission rate of under a few gigabits per second.
The band is essentially undeveloped and available for use in a broad range of new products and services, including high-speed, point-to-point wireless local area networks and broadband Internet access. WirelessHD is another recent technology that operates near the 60 GHz range. Highly directional, “pencil-beam” signal characteristics permit different systems to operate close to one another without causing interference. Potential applications include radar systems with very high resolution.
The upcoming Wi-Fi standard IEEE 802.11ad will run on the 60 GHz (V band) spectrum with data transfer rates of up to 7 Gbit/s.
Uses of the millimeter wave bands include point-to-point communications, intersatellite links, and point-to-multipoint communications.
Because of shorter wavelengths, the band permits the use of smaller antennas than would be required for similar circumstances in the lower bands, to achieve the same high directivity and high gain. The immediate consequence of this high directivity, coupled with the high free space loss at these frequencies, is the possibility of a more efficient use of the spectrum for point-to-multipoint applications. Since a greater number of highly directive antennas can be placed in a given area than less directive antennas, the net result is higher reuse of the spectrum, and higher density of users, as compared to lower frequencies. Furthermore, because one can place more voice channels or broadband information using a higher frequency to transmit the information, this spectrum could potentially be used as a replacement for or supplement to fiber optics.
Bandwidth & Scalable Capacity
The main benefit that Millimeter Wave technology has over lower RF frequencies is the spectral bandwidth of 5GHz being available in each of the E-Band ranges, resulting in current speeds of 1.25Gbps Full Duplex with potential throughput speeds of up to 10Gbps Full Duplex being made possible. Once market demand increases and better modulation techniques are implemented, spectral efficiency of the equipment will improve allowing the equipment to meet the higher capacity demands of prospective future networks.
Whereas low frequency, microwave signals have a wide beamwidth angle which reduces the reuse of transmission of the same signal within the local geographic area, Millimeter Wave signals transmit in very narrow, focused beams which allows for multiple deployments in tight proximity whilst using the same frequency ranges. This allows a density of around 15 times more when comparing a 70GHz signal to a 20GHz example making Millimeter Wave ideal for Point-to-Point Mesh, Ring and dense Hub & Spoke network topologies where lower frequency signals would not be able to cope before cross signal interference would become a significant limiting factor.
Propagation & Signal Attenuation
In general, Millimeter Wave links can range in anywhere up to 10km depending on factors such as equipment specifications and environmental conditions. The propagation properties of Millimeter Waves are much like those of the other popular wireless networking frequencies in that they are most significantly affected by air moisture levels; atmospheric Oxygen is also a large factor in the 60GHz band but almost negligible in the other ranges, under 0.2 dB per km.
Water vapour affects the signal at between 0 and 3dB/km at high humidity levels and the propagation due to clouds and fog acts in a very similar way depending on the density and amount of droplets in the air. These losses are relatively low and only play a major factor when considering links at 5km+.
Signal Loss (dB/km)
Oxygen absorption at Sea Level
Humidity of 100% at 30°C
Heavy Fog of 50m visibility
Heavy Rain Shower at 25mm/hr
At the 70 to 80GHz bands, water, in the form of rain, plays the most significant role in signal attenuation as it does with lower frequency signals too. The rate of rainfall, measured in mm/hour, is the depending factor in signal loss meaning that the harder it is raining, the lower the signal strength will be. 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.
Signal Loss (dB/km)
The reliability of a Millimeter Wave Wireless Network relies on the same principles as any other, in particular, the distance of operation, the radio’s link margin (being factors of transmit power, receiver sensitivity and beam divergence) and others such as redundancy paths. A link may be heavily affected by a period of intense rainfall but if it has a large enough margin, it will not suffer an outage.
The reliability of a network is called the availability and is measured as a percentage of time that the network will be functioning, for example, an availability of 99.999% over a year will equate to just over 5 hours of downtime. Much research by the ITU (International Telecommunication Union) has gone into collecting rainfall date from metropolitan areas around the world and how it will affect Millimeter Wave transmissions. You can see below an example of the expected availability of a widely available Millimeter Wave link for a few global cities and their respective availability for a 2km link.
Link Range (km, at 99.999% Availability)
Availability (2 km link)
Security is also an issue when dealing with wireless transmissions but due to Millimeter Wave’s inherently low beam widths (“pencil beams”) at about 0.36° radius with a 2ft. antenna along with, generally, lower peak transmit powers relative to lower frequencies the technology has a low probability of intercept and detection which is vital for the transference of confidential material.
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We include technology introduction papers as well as usage cases to guide users in the very latest in Gigabit Wireless technology and deployment. Modern wireless products can reach 10Gbps or higher capacity.
Applications for Wireless
Gigabit Wireless networks are used in a wide range of applications which include
4G/LTE Backhaul Networks
Last Mile Networks
Security and CCTV
If you are considering a wireless network with 10Gbps or higher capacity, please ask our team of experts who will be delighted to assist: