Print Friendly, PDF & Email

Names have been removed from this article at the request of the police department.

One of the most difficult decisions that a police chief will ever make is whether or not to pull the plug on very expensive technology that isn’t doing the job. Such was the case in August 2007 when the chief of a medium-size police department in California gave the order to stop using the county’s digital trunked radio system and return to the City’s own analog radios that were almost 20 years old.

In 2003 the Anonymous Police Department (APD) accepted an offer from the County to participate in the County’s brand new Motorola digital trunked radio system. APD staff thought they were embarking on a project that would upgrade and improve radio coverage and reliability. Motorola and the County assured the APD management team that the new system was the best possible radio communications system available. APD made an effort to adapt to the trunked system’s shortcomings, but the compromise was too great when lives of first responders were on the line.

APD police officers and dispatchers reported chronic radio communications problems starting in December 2004 when the Department first began using the system. The Department switched dispatch operations back to its old analog radio system on several occasions while engineers and technicians attempted to correct the problems. Improvements were made, but some problems could not be solved.

The County’s trunked radio system initially had severe coverage limitations in APD’s service area, even though Anonymous City is the county seat. This was improved when the County invested about $500,000 to add additional radio infrastructure at the Hall of Justice in 2005. Coverage improved, but overall system performance still hampered Anonymous police officers from safely doing their job.

Our staff has spent considerable time listening to the County digital trunked radio system and analyzing its control channel data. We conclude that most of the problems experienced by APD are endemic to the digital trunking concept. These issues include:

  • Frequent garbled transmissions, possibly due to fading caused by multipath interference.
  • Inability of the digital vocoders to distinguish human voice from background noise.
  • Slow system key-up. It takes a long time from when the button on the microphone is pressed until an officer can be heard. This is extremely frustrating to a police officer who has an urgent message to communicate.
  • Software defects that are not identified prior to live operation in a mission-critical environment.

In addition, the following system-specific issues contributed to the problems experienced by APD:

  • Insufficient digital trunked voting receivers to provide good in-building coverage for handheld radios.
  • Manufacturing defects in handheld radios that were allegedly corrected through the manufacturer’s warranty process.
  • Comparatively short battery life for portable radios.
  • Problems with change management policies and procedures that resulted in unpredictable system performance due to inconsistent software versions and technician error.

There were a few cases of catastrophic system failures due to technician error or hardware failure.

APD police officers are extremely pleased to be back on the old analog radio system for good. They report dramatically improved confidence when using the analog radio system, with none of the problems associated with digital trunking.

Anonymous Police Department intends to upgrade its three multisite voted UHF T-Band radio systems and convert them to analog narrowband prior to 2013 in order to meet the FCC requirement for 12.5 KHz spectrum efficiency.

Anonymous City is a community of about 75,000 people in the State of California and covers about 20 square miles.


Chronology of Events

02/2003 The County scheduled its trunked radio system implementation for February through March 2003, cutting over one department at a time. EMS and the Sheriff’s Office would be last on the schedule. Most of the County departments cutover on schedule; however the Sheriff’s Office and EMS did not.

The Sheriff’s Office and EMS did not cutover on schedule because of numerous issues with trunking and dispatch console integration. The Sheriff’s Office completed its migration to the trunked system in March 2004 and the console patch between the Sheriff’s Office digital trunked talk group and its old analog system was disabled.

03/2003 Anonymous Police Department (APD) begins talking with the County and Motorola sales people about using the County’s digital trunked radio system.

10/2003 The Gold Elite dispatch console at APD is connected to the County’s Embassy Switch. Documents are prepared whereby APD would pay the County $687,000 for “buy in” to the digital trunked radio system, plus monthly subscription fees for each of its mobile and portable radios. Additionally, Anonymous Police Department would spend more than $1,000,000 to purchase mobile and portable radios, and to upgrade its Gold Elite radio console.

07/2004 EMS migrated to the trunked radio system. The delay for EMS conversion was caused by problems with the “ring down” feature not working.

08/2004 There were numerous problems with the digital trunked radio system between August and December 2004 that include bleed over, unexplainable system failures, and resources disappearing from the Gold Elite dispatch consoles.

The problem with resources occasionally disappearing from the Gold Elite consoles still plagues the system today (2007).

12/2004 APD began using the digital trunked radio system. Numerous issues related to operating two dispatch centers on the same system became apparent.

02/2005 APD moved dispatch operations back to its old conventional analog radio system because of coverage and reliability problems with the digital trunked radio system.

09/2005 The new $500,000 digital trunked simulcast radio site at the Hall of Justice is placed into service.

02/2006 APD begins testing the updated digital trunked radio system after the new equipment had been added at the Hall of Justice site. APD switches to/from the trunked radio system numerous times, and only for certain days/times or work shifts. A few weeks later, APD moves dispatch operations back to the digital trunked system.

08/2006 APD goes back to its conventional analog radio system due to inconsistent performance of the digital trunked system.

10/2006 A manufacturing defect is identified in the Motorola XTS3000 portable radio that affects approximately 25% of APD’s radios. This is believed to be one of the causes of poor audio quality. These portables are repaired under warranty.

11/2006 APD resumes use of the digital trunked system after receiving assurance from Motorola that the system problems had been corrected.

08/2007 APD continues to experience coverage problems, significant keyup delay and frequent reports of garbled audio.

APD permanently disconnects from the County digital trunked radio system. The APD Gold Elite console is disassociated from the County’s trunked radio system. APD mobile and portable radios are removed from the trunked system’s list of authorized subscriber devices.