By Rick Pray
President
RPA Electronic Solutions, Inc.

RPA Electronic Solutions is a regular exhibitor at the Interservice / Industry Training, Simulation, and Education Conference (I/ITSEC) in Orlando, Florida. This year, one of our customers asked us to show a new man-wearable wireless system that we had developed as part of a US Army SBIR effort. That system allows a trainee using a Helmet Mounted Display (HMD) to operate un-tethered, communicating high resolution video, motion tracking device data, and simulated weapons cues to and from the trainee with minimal latency.

From past experience at the I/ITSEC conference, we have found the WLAN space to be saturated with wireless devices from the nearly 1,000 exhibitors. The show does provide a vendor who works with exhibitors to attempt to ‘manage’ the RF spectrum in order to minimize interference between users of similar Wi-Fi LANs. But, this works only as well as the exhibitors provide their information. Many do not subscribe to the RF management service and thus interference between booths becomes a potential problem.

RPA’s approach was to avoid this problem by incorporating a RF shielded room within our booth. The planned demonstrations were extremely important to both us and our Army customer.

We initially purchased some low cost material to test WLAN attenuation and found it completely unsuitable. Our research then led us to the Kaltman Creations Aaronia-Shield® material, which boasted much higher RF attenuation in the 802.11g and 802.11n RF space, which is where our equipment would operate. This also happens to be the space where most of the other exhibitor’s WLAN equipment would operate.

We purchased a small amount of material first to test in our engineering lab, given the disappointment of the first material we tried. We were very pleased to discover that we could isolate a set of wireless LANs operating both inside and outside the material, and that the equipment inside the shielded environment would not connect to the WLAN operating outside that space. This gave us confidence to proceed with our shielded room plan for the I/ITSEC show.

We contacted the show RF vendor, and they were very pleased with our approach. They even waived the usual fee they charge for RF management given our test results.

Within the shielded environment, we operated a 802.11g LAN and a WHDI based subsystem for high resolution video transmission. Both operated flawlessly throughout the four day conference. We were visited by other companies that had also attempted to operate similar setups, using WHDI and wireless motion tracking devices with HMDs. These exhibitors had great difficulty with their systems, and achieved only sporadic operation because of the interference from other displays. Some of the other exhibitors brought their visitors to our booth to see a successful system operation, and have since decided to promote our integrated video, motion, simulated weapon, and other sensor data solution with their HMD systems.

The Aaronia-Shield® worked flawlessly during the entire conference and gave us the ability to fully demonstrate our training solution with great success. Our Army customer was also very pleased with the results.

RPA's trade show booth (left photo) with the shielding room, shown free-standing in right photo.

In our increasingly crowded Radio Frequency environment, we are hard pressed to deliver functional wireless systems and often are pressed into sub-rentals and additional purchases to solve problems with spectrum and frequency availability. This year, at the 2007 Infocomm show, I discovered a new product that makes accessing the RF spectrum information by running real time frequency analysis affordable.

We have often relied upon a very unscientific process by which we hunt and guess for wireless frequencies. This year, looking ahead to our large industrials, I realized that we were in difficult times trying get all of our wireless solutions to work as planned, especially for an upcoming show in Boston. We decided to push forward with a scanning system as we packed in progressively more and more wireless channels into our limited spectrum. The weekly rentals for scanners, as typically used in New York on Broadway, are upwards of a $1,000 dollars plus a tech to operate. We needed an affordable solution to manage monumental amounts of wireless. The bottom line, the Spectran HF4060 made it possible for us to take 140 wireless Mic, Com, and IFB channels to the AARP National Convention in Boston, Massachusetts, and they worked flawlessly.

Features: The Spectran HF4060 covers the frequency range of 10MHz to 6GHz making it possible to view all RF activity from down around 70MHz – 80MHz for assisted listening devices through VHF & UHF, all the way up to 6GHz. On the higher frequencies, you can view RF activity for remote AMX and Crestron wireless control, Wi-Fi, intercom, etc. Just likes its counterpart’s – models HF4040, HF6060 and HF6080 – the Spectran HF4060 features 10 users assignable Hot Keys for instant access to frequently used RF bands, plus you can manually input any frequency start and stop point. There is a jog dial on the side of the unit which positions a cursor on the LCD screen and the cursor position is readout in both frequency and level in dbm. Clicking this jog dial allows you to zoom in to a high resolution, close-up view of the RF activity, finding offending interference, available RF space, etc. There is a whole suite of menu items such as resolution, sweep time, antenna types, etc., but the default’s which were set by Kaltman Creations (the US distributor), seem to cover all of our Pro Audio, AV related needs. All of these functions, and more, are also available via the included PC software.

“The bottom line, the Spectran HF4060 made it possible for us to take 140 wireless Mic, Com, and IFB channels to the AARP National Convention in Boston, Massachusetts, and they worked flawlessly.”

What I Like About It: Looking ahead to the Feb 2009 analog TV cutoff time and the pending RF auction to the larger wireless provider’s means that the RF congestion problem will only be more complex as we move forward. Tools like the HF4060 RF spectrum analyzer will be critical to our success and our ability to use our current arsenal of wireless equipment and make informed decisions about what to buy in the future. I have suggested that MSI’s growing installation department will also host this device, as their needs may well exceed the rental and staging department’s need. Aside from handheld operation, the Spectran HF4060’s USB computer interface and included software means that you can scan a frequency range in advance of firing up your first wireless device. I set the unit up on the day of our technical installations and found nice spectrum holes for our equipment to working in, which confirmed a lot of the pre-production work we had done. But, I also found that a local station in the Boston area had switched on their DTV transmitter and that none of the usual frequency allocation places had this information documented.

What I Would Change: I would like the system to have a BNC antenna connector, or at least an included SMA to BNC adapter, so that I could plug the unit into an output of a typical wireless microphone receiver antenna distribution system. This would permit me to use the analyzer to set up the antenna systems to maximize what I need and minimize background signals. I would like to be able to create some markers in the software interface so I could track a challenging area over time. I would also like to be able to hone into an area for a detailed look while still sweeping the wider band.

Summary: Spectran HF4060 RF spectrum analyzer has earned a place in my workbox. One of the key challenges for these events was working around the RF interference while still providing a flexible presentation solution to our high profile presenters. I strongly suggest the HF4060 system for any dynamic and uncontrolled RF environment where you really need your systems to work.

Product Reviewer: Ken Freeman, Technical Sales Manager with Meeting Services Inc. MSI is a full service Audio Visual Staging rental supplier and systems integrator with over 50 years in the business. Over 120 employees call their 70,000 square foot warehouse and offices home base. MSI is located in Southern California at 9220 Activity Road, San Diego, CA, 92126. Ken can be reached at 858-348-0100, faxed at 858-348-0076 and on the web at www.msiprod.com.

“The bottom line is that the Spectran HF4060 is an outstanding RF tool.
This thing just plain works!”

This past football season the Kaltman Creations’ Spectran HF4060 RF Spectrum Analyzer has become “the tool” that has allowed us to be one of the first, if not the first, NCAA venues to offer RF Frequency Coordination. Unlike bulky and extremely expensive bench analyzers, the Spectran HF4060 is an affordable handheld unit which has provided a solution to every one of our RF problem thus far. Whether we’re trying to find a slice to stick our 2.4 GHz wireless video into, or making sure that our coaching wireless intercoms are free of interference, this little unit has proven to be invaluable.

We primarily use it while connected via USB to a Sony Ultra Mobile PC. The Spectran’s PC software offers a great visual display and controls that any typical Windows user can easily manipulate. If one wanted, the software can be designed to accommodate specific custom templates to suit a particular venue or event. Below is a list of recent events and activities where the HF4060 helped to insure and protect the stability of our RF transmissions and abate any potential RF interference:

• The Texas Aggie pre-Game Show – Radio
• KBTX Pre-game Onsite Show – TV
• The Aggie Band Show – Video
• Home Team Coaching Wireless Intercom – Intercom
• Visiting Team Coaching Wireless Intercom – Intercom
• Aggie Sports Network – Radio
• 12th Man TV Wireless Intercom – Intercom
• Big Screen Wireless intercom – Intercom
• Big 12 Referee Mics – In Game
• ABC / ESPN / Fox Sports Net Wireless Mics and IFB – TV

It is also interesting to note that all of these events and their different frequency coordination needs occurred at the same day within a 6 hour window.

In all, we manage approximately 125 different wireless frequencies – in the 10MHz to 6GHz range – for any given football game. So far this year it’s been smooth sailing. We have had zero reported RF interference issues from any of the parties involved. All of this good news is based upon the use of the HF4060 analyzer which has allowed us to look at the available spectrum, assign frequencies as needed, and coordinate comfortable channel spacing.

The HF4060 system includes several accessories including a LOG Periodic Directional Antenna. We had the opportunity to break out the directional antenna and play “RF Detective” to track down the occasional Reporter or Photographer who grabbed a wireless unit out of their van after going through the frequency coordination check point. Luckily these individuals were not on a frequency that was of harm to anyone and we were able to quickly identify and reserve those frequencies for them. While being an RF Sleuth sounds like an easy process, at times it can extremely difficult. Few reporters and photographers have broadcast engineering backgrounds and they may not fully appreciate all of the potential RF interference issues. So at times it may seem to be a real “pain” for them to bring us their RF gear and let us analyze it to determine their frequency. But once the different media outlets realized we were helping to protect their broadcast signals as well as our own, they seemed to be pleased to comply. We are also very lucky to have the support of our Sports Information Director and Director of Game Operations. “If Aaron and his little whiz-banger analyzer doesn’t give you a clean bill of health, then no pass or access to the game.” This kind of support has proven to be the key to fool-proof frequency coordination.

The bottom line is that the Spectran HF4060 is an outstanding RF tool. On a range of 1 to 100, I give it a 99. Yes, it is that good. This thing just plain works! The unit works well with any emitting RF signal; even the Bluetooth keyboard I am typing on right now. If it’s an RF signal between 10MHz and 6GHz this thing can see, smell and taste it!

One final note: not only has the analyzer been great to work with, but the folks at Kaltman Creations have the expertise to help design an “RF plan of attack.” Need some help in the use of the analyzer, they can help; can’t figure out your RF problem, they can help there too. These guys really know their stuff. Who better to look to for help in managing your existing or new RF airspace then the guys who sell the tools?

Reviewer: Aaron Creasy, Chief Engineer Texas A&M Athletics. Aaron can be reached at: 979-458-1255.