Antenna Verification Testing


Dave Adams is a Senior Product Manager for PCTEL. He is responsible for SeeGull® scanning receivers and SeeHawk® data collection software for cellular networks. For the last year Dave has collaborated with field engineers from tier-1 carriers and service companies, gathering feedback to find the pain points in their Distributed Antenna Systems (DAS) and small cell commissioning and verification process. This led to a new feature called the «Antenna Verification Test» (AVT) in SeeHawk Touch, PCTEL’s Android-based application geared for in-building testing with the IBflex® scanning receiver.


Joe: Dave, you’ve been out meeting with network engineers nonstop. Welcome back. Without stepping too much on the upcoming Antenna Verification Test (AVT) online seminar, hosted by the North East DAS and Small Cell Association (NEDAS) on February 21, can you summarize what you learned while you were out in the field?

Dave: We encourage everyone to register for the seminar for all the details on the how. Today I’ll give some background on the what and why.  With 80% of mobile traffic now in-building, carriers are installing DAS and small cells to provide coverage and capacity to their customers. We had many opportunities to work with carriers and DAS neutral hosts to be on-site while in-building testing of the network was conducted. It stood out that much of the activity was verifying that the system was built as designed.  The recurring question was: «Did the antenna system and network equipment get installed and configured correctly? And can I verify this without a full walk test?»

Joe: Is a standard walk test the only way? How is it done?

Dave: They use what they have in their kits. Traditional test tools: scanning receivers, UEs, collection software. These can be used to conduct a walk test and verify the installation of the small cells or antenna system, but up to now there’s been no solution in the market specifically tailored to perform these tasks. Without a way to focus on these «spot tests» at the start, using walk test gear has been the way, typically with two engineers. This isn’t the ideal way to approach it.

Different versions of «Before I spend hours walking an entire building, I want to verify the antenna system and network equipment was installed and configured correctly.» is what I heard again and again.

The question that needs to be answered is, «is the signal level for each band coming from the antennas within an acceptable range of what the network was designed to provide?» There has been universal agreement this is the required measurement and the right tool would greatly streamline the verification process.

Joe: How to streamline that process was the genesis for the Antenna Verification Test feature in PCTEL’s SeeHawk Touch data collection software?

Dave: Exactly. We’ve been working on it side-by-side with the carriers along the way. Watching them work, taking measurements side by side with them.

Joe: So AVT is like a health check? It quickly identifies which antennas or small cells have a problem?

Dave: Yes it is like a health check, so if there’s a problem with the basic setup it can be addressed before doing an entire walk test. The walk test of course still has its place, but all of those detailed measurements that take a long time to collect are not meaningful if the hardware hasn’t been installed correctly or there are mistakes in configuring the equipment.

Joe: At what point of the testing lifecycle is it executed?

Dave: This would normally be done once after design and installation of DAS equipment, and again after the cell sites or small cells have been configured, before any optimization testing.

Joe: Can an Antenna Verification Test apply to other network types than DAS and small cell?

Dave: Wi-Fi, O-DAS, any HetNet. It could even work on macro networks based on the measurement requirements. If there is an antenna the AVT can verify it is working as intended.

Joe: If this test is ignoring the usual KPIs, hand-off conditions, etc. of a standard walk test, what exactly is it measuring? What am I looking for?

Dave: The engineer measures at the location of selected antenna or small cells. In the case on DAS antenna installation completion, the power level is measured to match to the level expected from the design. After network equipment has been configured, the measurements provide immediate performance results including the best serving pilot, cell ID, interference, and power level. All measurements are displayed specific to each location.

Joe: And I can go straight to the handful of spots where I care only about the signal from a specific antenna instead of having to do a tedious and time consuming walk to plot dots over the entire map?

Dave: You can move right to the locations you want tested. It is critical that the collection tool has the complete transmitter information (DAS antennas or small cells) to accomplish this work. This requires full integration with the planning tool of choice. Through AVT mode in SeeHawk Touch, the IBflex takes the measurements, creates the desired report documentation and sends back immediate results – within a few seconds. The results can be judged against set benchmarks, or compared to other antenna locations that have been tested. In the seminar we will cover some of the automatic checks we are performing, enabling experienced engineers to find and fix problems quickly.

Joe: The feedback from early users has been great. Now that PCTEL’s AVT has been released are you going to be able to cash in any of those frequent flyer miles for a vacation before all the «We love it! Now here’s a list of new feature requests…» start rolling in?

Dave: We hope everyone loves it. Maybe I’ll get a little time away after the seminar. That’s step one to make sure people understand what AVT can do and how to get the most out of it. It will be a virtual demo, explain a few ideas for the future, like uplink testing, and take questions and suggestions. Feedback is always welcomed. We’re here to make our customer’s tests easier.