Tuesday, June 3, 2014

Meet the Rip Snorting, Fire Breathing 2.5 Gbps E-band Radio by Huawei

Huawei just upped the ante in the E-band radio market with their RTN 380. We just installed the very first of these links in the U.S., and so I’ll give you my impressions in my next couple of entries.

It started with a unique application where we had antenna space for only a single 1-foot dish (sandwiched between two existing ones), but we needed to get twice the throughput as advertised by leading E-band vendors1 The customer is a genetics testing lab, where a single robot wants a 2 gig/second pipe, but if you Google leading E-band vendors you’ll see that their radios all top out at 1-1.25 Gbps 

A few uncomfortable weeks passed without a solution and then I saw an email from Huawei’s Seattle office, introducing their “2nd Generation E-band microwave”.  It was the 2 Gbps solution I was looking for! But, a Chinese radio? Holy ghosts of Fessenden, Marconi, de Forest and Tesla! What do the Chinese know about microwave?  Well a lot, actually. 

The Huawei radio is heavier with an ODU that's maybe 15% larger than other E-band radios, but it's pushing twice the throughput too. It's a solid ODU package made to withstand hurricane forces (maybe an asteroid attack), and seeing it coupled with a familiar high-performance Andrew dish gave me added assurance. The mechanical design is well thought out too, so that for instance, it’s impossible to screw up V and H polarization. (Imagine the service calls they don’t get.) And, they have an ODU combiner that lets you to hang a second ODU from it, and so now you’ve got a potential of 5 gigs/second across a single set of 1’ dishes. Call it what you will, but the RTN 380 is a game changer.

The shipment came with an installation manual with large, 11” x 17” pages, and so I had an impulse to tear it apart and tape it up on a wall, page by page.  The manual is comprehensive and leaves nothing to chance, including that the installer may not know how to properly tape up and weatherproof a connector or ground parts of the system.

Huawei’s attention to the installation is notable. They furnish everything you need to install and weatherproof their radios, down to various color and sizes of tie wraps, including ones that hold several times the typical 75-pound tensile strength.  Whatever supplies came with the shipment (e.g., electrical tape and butyl, tie wraps, pre-made grounding straps, clamps and tools) saved at least one trip to Home Depot.

Ironically, the one thing missing was power supplies. Huawei builds these radios for carriers and in that environment they expect to see DC power (or PoE switch ports that go to 55-60 watts), and that's not what you’re going to find in typical enterprise setups.  But fortunately we found power supplies from Mean Well that readily met the specs we needed.

Otherwise, the antenna mount is typical of carrier-grade microwave products, heavy-duty and with easy to access fine adjustments for azimuth and elevation. And the ODUs attach with ease, with a guide bolt and spring captured allan screws that aren’t going to fall out if you’re up a tower.  

Huawei's RTN 380 E-band PTP Wireless Link
Huawei's RTN 380: 2.5 gigs across a single 1' Dish
For our 2 gig payload, we ran one cat-5 and one fiber. I would have liked both gigabit handoffs to be cat-5, but the fiber was already cut, connectorized, and in a protective jacket that made it easy to run. Outdoor (ODU) connections are each contained in “waterproof sockets” and let me tell you, nothing’s getting into those connector ports. The waterproof sockets are the same used on commercial aircraft, a point that Huawei likes to emphasize.  Still, I don’t like custom cabling and would rather buy it off the shelf, cut and terminate it myself and find a different way to do the waterproof sockets. I like the way Siklu does their "weatherproof glands".

The two gigabit cables (a cat-5 PoE, and fiber) go from the ODU to a power injector (PI) for ground and lightning protection, and from the PI we ran a 2-conductor DC wire to the AC/DC power supply and added a second cat-5 for out-of-band management.

Once everything was connected we powered the radios and were pleased that they didn’t interfere with two other 80GHz links that were previously installed. (The RTN 380 has a built in spectrum analyzer to tell you that, but I wasn’t taking any chances.) And so we started up in low power (-10dB), and though it's a mere .7 degree beam coming from the dish, eye-balling them gave us an instant -55dBm reading. We aligned more at both ends, raised the power from -10dBm to +2, and then we were running at -30 dBm, which can be a bit hot for some radios. Huawei claims their radios can actually run at -25 or better without overloading, but still, I felt better leaving the radios at around -32dBm.  The customer's path is only 800 feet so they’re never going to feel a rain fade, and they haven't yet with the two Siklu Etherhaul radios we installed months before.

Here’s my assessment of the RTN 380 on a scale of 1-10

Product sheet:  10
Someone’s hiring our top English majors.

Install manual: 9
I'll be jerk and give it a 10 only if it was on tear resistant, waterproof paper.   

Furnishing install supplies: 10

Protection afforded by the waterproof sockets: 10 
Convenience/Install flexibility of the waterproof sockets: 0

Having no AC power supply: 3 
Huawei gets 3 points for having a radio that wasn't hard to find a power supply for. 

Mechanical Design: 8
Don't look for it at MOMA, but their ODU can survive a fall from space.

Pipe Mount: 10
It’s small enough that it doesn’t overwhelm a 1-foot dish, yet it could hold a 6-footer.

Power Injector: 7
Functionally perfect and obviously high end, but the opening for the custom power and Ethernet cable is too narrow and so you just barely can get a couple of threads on the allen screws to catch enough to close the box. 

Built-in spectrum analyzer: 9 
I’d give it a 10 for a more eye catching display, but a 9 for having one in the first place. 

Single Link 2.5 Gbps Throughput: 10 
5 Gbps potential throughput with a 2nd ODU: 10

So my first impression of the RTN 380 is a very pleasant one. It solved our bandwidth problem and it seems to be a solid, well made product that we feel confident about, and that our customer approved on sight. Installation went over without a hitch, after the shock of finding that we had no power supplies. But hey, what first time product deployment is ever complete without a surprise? The system is rock solid, definitely safe from the elements, the power injector is a nice unit (better when they get it to close all the way), and a lot of thought was put into the product. Huawei was good to work with too, attentive and very dedicated, and for added measure they gave us one of their engineers for on the job training. Thank you, Zhijun! 

Stay tuned for my follow-on, reviewing the RTN 380’s management interface, which I purposely haven't touched on yet. Spoiler alert. It’s Java based, but there are some very cool features too, like the spectrum analyzer that proved handy for us. Our customer has also offered to unleash terabytes of data at the link and so I’ll let you know how that goes.  


1 LightPointe is the only U.S. exception; the only E-band vendor I (later) found that matches Huawai’s 2.5 Gbps, single radio throughput.  They also offer an ODU combiner for double the throughput across a single set of dishes. LightPointe’s retail price is higher, and otherwise we didn't get to consider them, because Huawei never stopped trying to earn our business.  

#Huawei microwave #PTP wireless #RTN 380 #E-band radio #pointtopointmicrowave #microwavecommunications #wirelessindustrynews #wirelesswan


  1. What is the price range on the units?

  2. Hi Gino... Huawei's hasn't made list pricing public and so we're not at liberty to say. Generally, there's a good balance between bandwidth and price. You're getting double the bandwidth of a typical "1st generation" e-band radio, but for nowhere near double the price. Sorry I can't be more exact here.

  3. Do they have a special tool for link alignment other than the conventional multimeter.

  4. ALFOplus80HD from SIAE microelettronica it is little beter ...it's available with 2.5Gbps Radio capacity but also with a 2.5gbps port ...so single cable installation ::AMAZING idea ...https://www.siaemic.com/index.php/products-services/telecomsystems/microwave-product-portfolio?id=281