A public safety radio system by Harris Corporation, similar to the radio system installed in Naperville and Aurora has been put on hold in Miami-Dade, Florida. After glitches, garbled conversations and dead spots were discovered in a $25 million radio system, the law enforcement agency in Florida is reverting back to an older analog radio system by the end of this week.
In the last two weeks, Miami-Dade police officers reported transmission delays, garbled conversations, echoes and “dead zones” where the system doesn’t work properly — especially for public safety applications.
The encrypted system puts an extra layer of complexity in public radio systems. First analog voice is converted to a digital signal, which is transmitted in a complex system to handle multiple voice communications using talk groups and several radio frequencies. Secondly with encryption, a key code is sent with the digitally converted voice signal. If the key does not fully transmit, the voice communication is not accepted. In this case no voice communication will be heard at all. If the key is transmitted but the digital voice communication is not complete, the voice sounds distorted or “skippy” and is often not intelligible. Many police agencies communicate this condition as “going digital” and the condition is often corrected by moving to a better location. Sometimes there is no easy solution, such as moving a few feet from the disabled location. Communications are then delayed, and in an emergency situation this, of course, could be dangerous.
Police officials in Miami-Dade have told the county commission that they are confident Harris Corporation can fix the problems.
However some systems in other metropolitan areas have not worked out well. The Harris Corporation’s radios failed during a visit by President Barack Obama in Oakland, the radios have received much criticism in Milwaukee’s police department, and the entire system was dumped after a waste of a $42 million in a failed attempt to install the radios in Las Vegas. One of the complaints was too many dead spots — very likely caused by the large buildings with nooks and crannies in casinos.
Sample problems reported in Naperville, Illinois (Harris Corp System)
• “Keying up” a radio, or attempting to communicate over it, has activated lights and sirens in police cars, including undercover vehicles.
• Keying up a radio in a Naperville electric utility substation inadvertently activated a switch and temporarily cut power to 1,200 customers.
• Naperville firefighters lost all communication with crews inside Naperville Central High School during a small fire on Feb. 28.
The police radio system used by Northwest Central Dispatch System (NWCDS) for Arlington Heights, Schaumburg and other northwest suburbs is manufactured by Motorola. However, the Motorola system is also encrypted and uses TDMA technology, which is a sort of time-sharing management of voice communications. According to police administrators, the radios tested well, and were rolled out with only minor delays. However, there have been reports of systemwide failures of the consoles in the NWCDS dispatch center, and the TDMA digital radios have very poor voice quality. Most male voices sound very similar, so it is sometimes difficult for police officers to fully understand who the other police officers are that they are talking to when radio signatures (car numbers or beat numbers) are not used during a voice communication. Also, the voice communications are not dynamic, and police officers complain that it is difficult to detect nuances in a fellow police officer’s voice that might indicate duress or other problems at the other end. Female voices also sound similar to all other female voices.
Schaumburg police even turned off encryption for a day to see if voice quality improved. It didn’t, so it is possible the voice quality problem is caused by the “latest” technology — TDMA itself.
Police officers have also complained of trouble with variable volume of the radios. Some police officers have even missed assignments and had to resort to cell phones to make sure they get their police call assignments. Also, the radios can spontaneously be too loud, which is inconvenient or possibly dangerous when they are used in discrete situations or during tactical or covert operations. The variable volume problems could have two sources. It may be a problem with the TDMA technology. People who have acquired the latest scanner technology radios configured to listen to non-encrypted TDMA public safety radios have complained of volume changing spontaneously. The volume problems may also arise from extra large controls on the radios that are accidentally adjusted, or by difficult coordination of the volume adjustment on the radio itself, and on the control on the speaker/microphone worn near the shoulder.
Fire departments in the NWCDS network are not using encryption, but are also using radios with the newer TDMA technology. Battalion chiefs, who do most of the talking on air, often sound the same, but this voice identity recognition issue is not as much of a problem in most situations, because only two or three battalion chiefs would usually be on the same talk group. Dispatchers have to be extra careful to understand which battalion chief is requesting, for example, extra fire engines or extra ambulances for an incident. Hopefully, the voice source is reinforced by a voice/unit ID on the Computer Aided Dispatch (CAD) monitor used by the dispatcher. Nevertheless, human voice recognition is still an issue and could very well be a critical issue in the case of a major incident or multiple simultaneous incidents. At the very least, the poor voice recognition capability constantly increases the mental load of dispatchers and first responders in maintaining situational awareness.
IMPORTANT ALERT …
Cardinal Note: When encrypted police radios are in use, police-response incidents are not reported in real time or within a prompt time period. Police protecting their realm of investigation and police activity, have chosen to use secret military-grade encrypted radios to withhold their police communications, which were previously open to the public and news media via monitoring of public safety scanning radios — with no known negative results locally.
The delayed knowledge or entirely blacked out knowledge resulting from encrypted police communications may protect certain police operations and investigations, but it also puts the public at risk in situations such as when armed and dangerous offenders are at large and when other similar situations occur, such as when desperate offenders of property crimes are eluding police. In other cases, the delayed or blacked out information inhibits or prohibits the possibility of the public providing early witness accounts before a criminal trail goes cold. Citizens are much more likely to recognize or recall suspicious or criminal activity if they are aware of the criminal incident within minutes or hours of its occurrence. The most serious incident involving dire results would be a trail that is allowed to go cold in the case of child abduction.
The lack of real time information from public police dispatch also weakens an effective neighborhood watch program mostly working to prevent property loss, but also working to prevent possible violent crimes.
Police have alternate ways to transmit tactical, operational or investigative information, while still keeping their main public dispatch channels open for the best balance of public safety and police safety.
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