First responders standardized on two-way radios for communication in the 1930s. Over the years, Motorola has done a great job of developing and iterating land mobile radio (LMR) technology, developing new features and functions that contribute to the effectiveness and safe operation of communications systems.
One significant challenge for public safety communication is indoor coverage, which is getting worse. LEED-certified buildings can attenuate (reduce) a radio signal by 30dB, rendering it useless and creating a dead zone where two-way radio signals can’t reach. (In a commercial cellular context, a dead zone is a location without cellular phone service.)
In a 2019 National Institute for Standards and Technology (NIST) report, dead zones were by far considered one of the biggest problems faced by Law Enforcement, Fire Fighters, and Emergency Medical Services (EMS) professionals. Communications breakdowns frequently make incident response more difficult to manage. One example is the unnecessary loss of life in the 9/11 terror attack in New York City, as messages were lost or went unheard between incident command and the first responders in the World Trade Center twin towers.
Following 9/11, Congress approved the development of a nationwide broadband safety network. In 2012 this network – named FirstNet – was formed and funded under the Department of Commerce. This nationwide network based on 4G LTE (cellular) technology would enable voice communications and offer mobile data capabilities to enable the use of new technologies in public safety, like vital sign monitoring and position location.
AT&T won the bid to provide the network to FirstNet and, in 2018, switched the network on. Ultimately, FirstNet will cover 2.74 million square miles and approximately 75% of the United States and D.C.
Today, both LMR and FirstNet (LTE) capabilities are available to first responders and public safety agencies nationwide.
PERFORMANCE LEADERSHIP FOR IN-BUILDING COMMUNICATION
In 2009, Nextivity shipped its first Smart Signal Booster product based on the company’s first proprietary chipset. As of 2020, no other in-building cellular coverage solution in the world has been able to match the performance leadership of Cel-Fi technology. With over 1 million units shipped, Cel-Fi technology has been battle-tested, network tested, and is trusted by 200 network operators globally. Nextivity is now shipping its 4th generation chipset and developing its 5th.
Having successfully disrupted the commercial cellular repeater market, Nextivity entered the public safety market in 2019 with its Cel-Fi GO RED product, where power, intelligence, and ease of install enables any and all buildings to eliminate FirstNet dead zones, providing reliable coverage for first responders.
CEL-FI QUATRA RED
In 2020, Nextivity begins shipping its Cel-Fi QUATRA RED solution. It’s the first concurrent dedicated FirstNet Cellular and Public Safety LMR In-Building Class A, Emergency Responder Radio Communications System (ERRCS) on the market. It supports FirstNet’s 4G LTE bands as well as the P25 / LMR channels in the 700 Mhz and 800 Mhz spectrum.
Cel-Fi QUATRA RED includes all the ERRCS system components and is ETL listed for compliance with UL2524. The system is modular, and comprised of the following:
1. Network Unit (NU). Also referred to as the Head End. This is where the external LMR and FirstNet donor signals are ingested and converted to digital for distribution.
2. Coverage Unit (CU). Commonly referred to as a Remote Unit. The CU is where the digital signal is converted back to analog RF, boosted, and retransmitted through an antenna to provide coverage.
3. Master Battery Back Up Unit (MBBU). The MBBU is not only a flexible battery backup system, it also houses the communications capability for the entire system and facilitates internet connectivity to the WAVE portal where all Cel-Fi systems are monitored. Dry contacts for the Fire Alarm Control Unit (FACU) are produced through the MBBU.
4. Remote Annunciator. Some jurisdictionswant the ERRCS Annunciator to be physically next to the FACU. Cel-Fi QUATRA RED’s Remote Annunciator allows for this and can be remotely connected to the MBBU via Category (Ethernet) cable.
5. Emergency Power Off (EPO). Cel-Fi QUATRA RED supports a separate EPO switch that can be installed with the main system in the fire room or placed remotely and connected via Category cable.
6. Active Server Antenna. The Cel-Fi QUATRA RED Active Server Antenna allows for monitoring and alarming of each individual antenna in the system.
An individual Cel-Fi QUATRA RED system can be deployed like a simple Bi-Directional Amplifier (BDA) or like a fiber Distributed Antenna System (DAS), depending on the size of space and needs on site. The QUATRA RED NU takes in the donor signal from the high site and distributes the signal over Category cable to the CU. Cus are powered over Ethernet (PoE), so not subject to additional backup battery requirements, and very easy to install.
Distributing the signal throughout the building from NU to CU using Category cable significantly reduces the installation complexity, relative to implementing a coaxial cable-based system. This makes the planning process much easier for installers, and reduces costs, time to market, and time to Certificate of Occupancy (CO).
Cel-Fi QUATRA RED relays First-Net Band 14, as well as bands 4, 12, and 25, depending on the band AT&T is broadcasting at a specific location. This provides for much more reliable FirstNet coverage, and can even provide FirstNet service where band 14 is not available.
Cel-Fi QUATRA RED features innovations never seen before in the public safety market and which differentiate it from other solutions – gain being one area where QUATRA RED stands out. The uplink gain setting on a booster is one of the determining factors in the signal strength received by the tower (i.e., the “high site”) and most jurisdictions have minimum and maximum requirements for received power level targets. Conventional BDAs and BDA-fed fiber-DAS systems have to be extremely careful with the gain settings in their systems. Too little gain results in pockets within the system where voice quality may suffer or could result in dead zones with no coverage. Too much gain could swamp the network, drowning out either the high-site or other neighboring systems. For these reasons, setting gain in conventional ERRCS systems typically requires highly skilled engineers, and plenty of trial and error. In contrast, because of the intelligence built-in to the QUATRA RED system and the ability for the system’s components to sense each other and understand their state of operation, gain can be set automatically at the touch of a button to simplify the process and eliminate the issues noted above. In addition, systems are remotely monitored, so in case of any post-installation issues, alarms will be triggered in the cloud.
As part of the Cel-Fi QUATRA RED portfolio, Nextivity has announced the Cel-Fi QUATRA RED Server Antenna. This simple-to-deploy server antenna can be monitored, so if the antenna’s connection is cut, the system will be alerted, and action can be taken. The QUATRA RED Server Antenna only works with QUATRA RED.
The Cel-Fi WAVE PRO app, which is used in commissioning Cel-Fi QUATRA RED, also includes an Antenna Pointing application that ensures the direction of the antenna is correct and will ensure the best possible donor signals are used.
The requirements for switching and gain control for a commercial cellular system are more onerous than that of public safety due to the number of users a commercial system has to support. With experience providing the world’s most advanced in-building cellular coverage systems over the past 10 years, Nextivity’s Cel-Fi QUATRA RED system guarantees the best talk-in and talk-out performance in the industry.
One of the challenges of the public safety ERRCS market in the United States is that each jurisdiction can interpret and enforce safety codes differently. This creates a substantial amount of variation from location to location, not just frequencies but also how specific standards are implemented. For example, some jurisdictions require 12-hour battery backup, and some require 24-hour battery backup. The Cel-Fi QUATRA RED system was designed from the ground up to be modular, to support all of the codes in a configurable manner.
For additional information on Cel-Fi QUATRA RED and its groundbreaking approach to in-building coverage for the public safety market, download this in-depth whitepaper: www.cel-fi.com/CRE30
About the Author
Joe Schmelzer has 20 years of experience driving the creation of products and solutions for chipset vendors, device OEMs, and service providers, including Sony, Qualcomm, Google, Verizon Wireless, AT&T, Dell, and HP. Mr. Schmelzer has previously held positions with Wavecom, Sierra Wireless, and Inseego. He was also a founding member of CTIA’s Wireless Internet Caucus. For more information, contact hello@cel-fi.com or visit www.cel-fi-com.
