Cliff effect danger?

With more agencies moving to digital voice systems, are police officers in danger of losing a signal because of the Cliff effect?

Cliff effect

In telecommunications, the (digital) cliff effect or brickwall effect describes the sudden loss of digital signal reception. Unlike analog signals, which gradually fade when signal strength decreases or electromagnetic interference or multipath increases, a digital signal provides data which is either perfect or non-existent at the receiving end. It is named for a graph of reception quality versus signal quality, where the digital signal "falls off a cliff" instead of having a gradual rolloff.

Cliff effect - Wikipedia, the free encyclopedia

If you use a digital radio you could lose your signal due to being out of range. This could be the PD, the FD, a taxi driver, or even a person cleaning an office building. If they use digital radios they may experience the cliff effect.

The issue with the cliff effect is the lack of warning. With analog you have a noisier and noisier signal to tell you the signal is about to be lost. With digital, and the associated cliff effect, things sound fine and then nothing.

This also makes scanner reception difficult at times, but people prefer to blame the scanner's manufacturer.

Usually instead of a sudden loss of intelligence, you'll get more and more errors until all you hear is garbage and then nothing. It does happen pretty quickly but you do get some notice before you lose it completely. If you're mobile then stopping will sometimes clear it up. The major drawback to digital communication though is the lack of redundancy. This is why a signal that is understandable though noisy on an analog channel might be completely unreadable on a digital one.

Digital subscriber radios can be programmed to alert users of imbalanced coverage in addition to a standard RSSI "bar meter" and out of range indicators. Imbalanced coverage alerts can be in the form of audible tones to alert the user of high BER.

It all comes down to user training and proper design, implementation and optimization of both the FNE and subscriber radios.

A poorly engineered system and poorly configured subscriber unit can be dangerous in IDLH environments whether digital or analog.