Although it has been somewhat ignored in the past, base transceiver station-to-DAS headend connectivity is now getting a lot of attention from manufacturers.
“Given the prevalence of DAS deployments, and multi-operator DAS installations in particular, BTS-to-DAS solutions are critical,” John Spindler, TE Connectivity director, product management, in-building DAS, told AGL Small Cell Link.
Historically, integrating base transceiver stations into DAS headends was done in a couple of ways. One was to take a hodgepodge of attenuators, splitters and combiners from different sources and assemble the cables and components on-site. Later the packaging was improved when manufacturers began assembling the parts and delivering them to integrators in a box, which made it easier because it reduced the installation time.
But both methods were passive. Any attenuation had to be made by manually turning the knobs, and there was no effective way to monitor it remotely.
The development of active integration panels (AIP) provides a new era of connectivity between mobile operator base stations and DAS with features such as remote monitoring and software configurable controls that improve system management, according to Spindler.
“In a multi-operator scenario, monitoring the downlink allows you to make sure that a single operator does not take more of the composite power than the other operators,” he said. “With a user- configurable automatic limit control on the downlink, you can avoid overdriving the DAS headend.”
With remote monitoring, in the case of a problem, the system may be fixed without sending a service tech. Diagnostics may be performed over the Internet, and adjustments may be made to the systems, Spindler said.
“If you cannot monitor these systems remotely and diagnose the problems, they are hard to maintain. This is a big step forward,” he said.
Active integration panels offer space savings, which may reduce the footprint in the headend by as much as 75 percent compared with traditional, passive attenuation panels. This solves the problem of space, which can be both expensive and scarce.
“You’ll see racks and racks of attenuation panels in large venues,” Splindler said. “Space is huge. Getting enough space for the DAS headend can be problematic in some places. With an AIP you get real estate savings from an opex standpoint plus the reduction in installation time and cost.
Active integration technology also reduces passive intermod by eliminating cabling and connectors and using components are low PIM, which is essential for LTE operations.
“With the advent of 4G and LTE, performance has really come to the forefront. Eliminating PIM is imperative so that DAS performs at its best,” Spindler said.