At a time in the not-so-distant past, there was only one way to implement microwave radio: one radio link per microwave terminal. Did not matter what type of link it concerned: protected, non-protected or multi-channel. From the advent of digital microwave radio in the 1980s and 1990s, terminals typically had no options for integration of co-located telecom devices. And to interconnect muxes or switches required external cabling and possibly a patch-panel.
Then in the early 2000s, so-called “nodal” radios came into vogue. Designed to address the drawbacks of the one-radio-one-link paradigm, a single microwave radio node could serve as a platform for multiple links. There were still limitations when it came to radio and switch interactions, but multiple sources of traffic could now be integrated and connected on the nodal platform.
Read MoreAs one of the most anticipated network technologies, Voice over LTE (VoLTE) has been discussed by operators for years. The expectation was that deployments would start in 2013, but roll-outs in North America were delayed.
Operators have faced a series of issues that include poor voice quality and long call establishment times. Once these problems are solved, it is expected that VoLTE will allow operators to provide voice and data services using an integrated packet network. As the problems described show, the implementation of VoLTE presents challenges for the entire LTE ecosystem including microwave backhaul.
We have produced a white paper to describe some of the VoLTE requirements that must be met in order to overcome these technical challenges, which must encompass a flexible microwave backhaul as a key factor for a successful transition to all-packet voice and video VoLTE networks. A brief introduction to VoLTE is presented and then different VoLTE backhaul requirements are described with possible solutions.
Click here to download a white paper on this subject titled “VoLTE and the IP/MPLS Cell Site Evolution”.
Read MoreCell sites will need to begin to transition to Layer 3 IP services. Photo credit: zdenadel / Foter / CC BY-ND
The entire wireless industry is on the cusp of a transitive time where Layer 3 IP services will be needed in the access portion of the network. And the backhaul will be needed to provide them.
Under the pain of restating the obvious, we have all seen the explosive growth of smartphones, tablet computers and other radio-frequency-loving gadgets like e-readers. All these new-fangled high-tech contraptions need Layer 3 IP/MPLS services in the access and backhaul in order to deliver a satisfying, seamless user experience—especially for enterprise services. The question is how will the mobile network operators (MNOs) be able to deliver these services from their thousands or tens of thousands of cell sites?
Typically, the answer would involve deploying a regular router for IP services at each and every cell site. But have you seen the prices of routers lately? Cisco didn’t get to where it is today without having some heavy pricetags attached to all the heavy iron it’s shipped over the last 20-odd years. Suffice to say, it would be a pretty penny if MNOs equipped all their cell sites with their own dedicated routers. So what else can be done, you query?
It just so happens that Aviat Networks’ director of corporate marketing, Gary Croke, has posted an article at RCR Wireless going over what to do in these types of situations. But we’ll give you a hint: the IP router function should be folded into a single multi-service, multi-layer cell site device. Read the rest and let us know what you think.
Related articles
Come Fly with Me: Aviat Microwave Over-the-Air at U.S. Landmarks (aviatnetworks.com)
The Rise of Tower Sharing in Africa (aviatnetworks.com)
How 2 Microwave Networks Survived Superstorm Sandy (aviatnetworks.com)
What Does it Take to Get the Most out of Your Wireless Backhaul? (aviatnetworks.com)
A quick Google-glance around the Internet will reveal a panoply of all-outdoor radios (ODRs) in both microwave and millimeter-wave bands. ODRs do not conform to a universal norm in terms of networking features, power consumption, bandwidth scalability (i.e., capacity) or outright radio horsepower (i.e., system gain).
So if you find yourself asking the questions, “Which ODR is the best fit for my network?” or “How do I narrow the ODR field?” it is good to start with the basics.
The right product choice can be quickly resolved—or at least the candidates can be short-listed—by focusing on three ODR product attributes that most heavily influence the value-for-the-money (i.e., total cost of ownership or TCO) equation:
For many microwave backhaul networks, the growth in underlying traffic is such that products which cannot scale to 500 Mbps/1 Gbps per channel will run out of momentum too early and precipitate the dreaded “forklift upgrade” (also known as the “CFO’s nightmare”).
These same CFOs are also suffering sleepless nights due to rising energy costs—which in some countries can double year-over-year. Therefore, it behooves the operator to seek and prioritize the use of über energy-efficient products, such as the Aviat WTM 3200, which—and this is important—do not compromise on RF performance.
That brings me to my last point: System gain (RF performance) remains a core TCO factor insofar as it can drive smaller antenna usage with the concomitant capex savings. Still, there might be little to differentiate ODRs in terms of RF performance—in which case the spotlight will fall on these other attributes to sway the decision.
Having worked on the operator side and wrestled with TCO analysis on many occasions, my experience tells me that you can narrow your ODR choice quickly by reflecting on these three attributes and the TCO gains they can deliver.
Jarlath Lally
Product Marketing Manager
Aviat Networks
A different solution to handle the burgeoning demand for mobile broadband capacity will be needed. More spectrum coupled with more spectral efficiency will not be sufficient. A clear solution is more sites, but deploying more macro-sites in urban and dense urban areas (where most of the traffic will be needed) will not be feasible.
Small cells promise a new “underlay” of outdoor and indoor, low power micro-cells that are deployed on public and private infrastructure within the urban clutter, are seen as seen as a likely solution. Sites being considered include:
These new sites will need to be compact, simple to install, energy efficient and incorporate an organically scalable and tightly integrated backhaul solution. As a result, there will be many more sites—some projections estimate that up to 10 small cells will be deployed for every macro-site. Small cells hold out the promise of great gains for the end users but massive challenges for the operators.
Small cell deployments so far have mainly been concentrated in Europe (3G) and the USA (LTE). 3G small cells may also be deployed in other regions as a means to avoid the difficulties in obtaining planning approval for larger macro-cell sites.
It’s Still Early
Today, as far as wireless small cell backhaul (SCBH) solutions are concerned, there is evidence of product immaturity and hyperactivity in equal measure.
There is profusion of aggressively hyped solutions, including many that are a rehashing existing/niche solutions and at the opposite extreme some very new and unproven technologies. In practice, these solutions are jockeying for position while operators grapple to understand the formidable planning and infrastructure challenges being thrown up by their small cell ambitions. It is apparent that few appear that they will fully satisfy the anticipated and emerging requirements in terms of performance (i.e., capacity, latency, availability), size/shape, ease of deployment and most importantly, total cost of ownership. For the complete article, download the PDF.
Stuart D. Little
Director, Product Marketing
Aviat Networks
Aviat WTM 6000 trunking microwave radio
Back in the day, trunking microwave radios were huge power-hungry beasts that consumed vast quantities of power and space at equal rates. They were complex “animals” that took days to install and hours to configure. Then they had to be looked after like well-loved but aged members of the family—with care, all due respect and consideration. Over time, components went out of adjustment and had to be brought back into line through various tuning routines, but overall they did their job as the super-reliable backbone of the POTS (i.e., Plain Old Telephone Service).
Jump forward a few decades and the latest trunking microwave solutions are elegant and graceful—almost svelte. With their current high levels of electronic integration, a complete repeater system can stand in a single rack space—unheard of until the most recent products. Furthermore, these new systems consume dramatically less power—a typical 3+1 system (i.e., four transceivers) consumes less than 400 watts. So now, backbone operators can save significantly on operating expenditure because of decreased space and power requirements at their microwave radio shelters.
Evolving microwave systems from analog to digital microwave systems carrying digital payloads was a rocky and dangerous path. The next migration from TDM payloads to IP payloads appears to be just as treacherous. How can a traditional TDM backbone radio, typically configured with N+1 radio protection switching, be reconfigured to transport a non-TDM payload that does not suit N+1 switching? IP transport is a completely different environment altogether! Luckily, trunking radio system designers have not ignored the Internet revolution and are perfectly aware of these challenges. In fact, well-appointed trunking microwave radio systems allow a graceful evolution from TDM to IP, with capability to transport both types of traffic simultaneously—and with their own ultra-reliable protection schemes!
Today, trunking microwave radios can support both TDM and IP seamlessly, offer robust radio performance and highly reliable switching and really do make it easy for operators to design mission-critical backbone networks. They offer mean time between failure (MTBF) reliability figures into the hundreds-of-years and highly integrated yet modular designs, which make expansion very straightforward. Before deciding on a trunking microwave radio, consider if the system:
Terry Ross
Senior Product Manager
Aviat Networks
As symbolized at the recent EANTC interoperability testing event, Aviat microwave radios can help solve the complexity and scalability problems of Carrier Ethernet technology.
Carrier Ethernet (CE) transport networks are growing in both scale and complexity, requiring both vendors and operators to deliver solutions to sustain their growth. To help address this, Aviat Networks recently participated in the European Advanced Networking Testing Center’s (EANTC) annual multi-vendor interoperability testing event to validate several aspects of scaling CE networks, among other things.
Increasing CE network sizes increase the complexity of management—especially from a services perspective—when CE services span multiple network domains. The ability to partition management domains and effectively manage alarms that accurately identify and propagate notification of network faults, dramatically speeds up the fault isolation and resolution process across large networks. Utilizing and effectively implementing “Hierarchical Service OAM” in growing CE networks is valuable to overcoming this challenge and was a key area of the recent interoperability testing.
Another critical aspect of growth is dealing with multi-technology—not just multi-vendor—interoperability. As CE networks scale, there is an increasing mix of Ethernet switching, MPLS and, most recently, MPLS-TP internetworking emerging. One potentially complex area that was also tested was validating the operation and survivability of intersecting Ethernet and MPLS-TP rings in a multi-homed topology. The “ERPSv2 and VPLS Interworking” test validated that standards-based G.8032 Ethernet protected rings and MPLS-TP VPLS rings can interoperate, or more significantly “co-operate,” to allow complex multi-technology networks to deliver reliable end-to-end services.
To learn about these aspects of scaling and dealing with complex CE networks check out the EANTC white paper for more details.
Errol Binda
Sr. Product and Solutions Marketing Manager
Aviat Networks
Aviat Networks’ Packet Node IRU600 is an example of an all-indoor microwave radio, which is one choice wireless operators should consider for implementations in North America.
There’s a lot of buzz in the microwave industry about the trend toward all-outdoor radios, but those who haven’t been through LTE deployments may be surprised to learn that based on our experience deploying LTE backhaul for some of the world’s largest LTE networks, all-indoor is actually the best radio architecture for LTE backhaul.
We can debate today’s LTE backhaul capacity requirements, but one thing we do know is that with new advances in LTE technology, the capacity needed is going to grow. This means that microwave radios installed for backhaul will likely have to be upgraded with more capacity over time. Although people are experimenting with compression techniques and very high QAM modulations and other capacity extension solutions, the most proven way to expand capacity is to add radio channels because it represents real usable bandwidth independent of packet sizes, traffic mix and the RF propagation environment.
All-indoor radios are more expensive initially in terms of capital expenditures, but they’re cheaper to expand and (as electronics are accessible without tower climb) are more easily serviced. While an outdoor radio connects to the antenna with Ethernet or coax cable, indoor radios usually need a more expensive waveguide to carry the RF signal from the radio to the antenna. So you pay more up front with an all-indoor radio but as the radio’s capacity grows you save money. There are several reasons.
When everything related to the radio is indoors, you just have a waveguide and an antenna up on the tower. To add radio channels with an all-indoor radio you go into the cabinet and add an RF unit. With an outdoor radio, you have to climb the tower, which can cost as much as $10,000. Also, when you add a new outdoor RF unit you may have to swap out the antenna for a larger one due to extra losses incurred by having to combine radio channels on tower….(read the full story at RCR Wireless).
Gary Croke
Senior Product Marketing Manager
Aviat Networks