SDR for Field Test Savings
Software Defined Radio (SDR) has created an opportunity for low-cost field activities with a single customize device. An SDR allows for multiple applications to be run over a single device and be expanded and customized by the end user. No longer are you tied to expensive RF hardware and chipsets for performing multiple common field activities. A single device could act as a scanner, UL transmitter, CW transmitter, spectrum analyzer and base-station tester simply by changing the software program running. This would include determining all available networks and types, common technology detailed scanning, parameter/site validation, coverage footprints, and transmit/receive path information.
Mobile Network Operators (MNOs) spend a fairly large amount of capital on hardware to test their networks directly or indirectly through subcontracted testing. Moving to SDRs could actually reduce test equipment costs by 60-70% over traditional equipment investments of today. Things as common as a network scanner to determine cell coverage. Operators typically pay for different capabilities in terms of technology and spectrum utilization. This is on top of individual licenses just to allow the use of this hardware capability. This is where SDRs make for savings with simple controlled software upgrades to allow for all spectrum, technologies, and bandwidths without changing equipment.
SDRs reduce the requirement of specialized hardware. A single module may address a wide range of uses, even those that are currently unknown. The design and construction of hardware has high overhead, but distributing software updates may have much lower associated costs. Using an SDR doesn’t lock a platform into a specific set of communications and functions. A simple update of the code (much of it opensource like GNU Radio) and the capabilities of the unit are updated and capable of whichever. SDRs are in their infancy in a way, but units such as HackRF One (~$300), BladeRF (~$400), USRP B200/B210 (~$700) and soon , Lime SDR (~$300) all offer cost effective SDRs supported by the OpenSource community and seem to have often limitless capabilities. This is in comparison to a full dimension rf scanner that may run into the tens of thousands of dollars.
There may not be the perfect product available today, but we seem to be on the verge of serious savings to the industry. The best part of an SDR is the life of the product. Unlike many HW based solutions that are quickly obsoleted by innovations in technology, SDRs have the ability to grow with technology. This allows a lesser upfront spend as well as less requirement for expensive equipment upgrades in the future. For instance, if you sell a first version of a product with say 802.11A standard, switching up to 802.11B in the second version could render original hardware useless. Customers will applaud if they can continue utilizing their old accessories after a simple upgrade. It’s entirely conceivable that such upgrades would be pushed over the air as is seen with mobile phones.
As the cost of SDRs continue to come down, the possible use cases goes up. SDRs will allow for the evolution of field testing beyond the technician and on to the all encompassing IoT. MNOs wouldn’t think of leaving a $30k scanner in every technicians vehicle, but a $1k unit that is completely up-gradable over the air and feeding back data automatically quickly becomes a test unit of possibilities. Network interference identification becomes not only a spectrum search, but can utilize programmable patterns and continually updated databases to identify common types and sources based on the data received. Machine learning is coming to drive-testing. Other activities are simple site/technology rollout observations, competitive analysis, parameter validation, general RAN network testing, CW transmit and receive, UL pathloss validation, fiber tests, microwave measurements, and countless other radio based measurements.
The software defined radio is still in the early stages of acceptance by the commercial community, but it will only be time before the cost savings potential of SDRs is realized by MNOs.