Clear-Com Tempest2400 - Manual (Page 15)

9 Tempest®24 00 2 -Channel Wireless Intercom System
With 2xTX technology, each audio packet is transmitt ed twice, each on one of two consecuti ve hops. The loss of one packet
transmission in a harsh RF environment is common. However, because of the quasi-orthogonal frequency relati onship of
the consecuti ve redundant packet transmission, the potenti al for loss of any single audio packet (2 consecuti ve data packet
transmissions) is dramati cally reduced. In additi on, each packet transmission is sent out from diff erent antennas. This
unique approach enables Tempest to uti lize spati al diversity, frequency diversity, ti me diversity and polarizati on diversity.
The 2-channel product does not operate with spati al or polar diversity due to the fact it uses a single antenna during
operati on.
Transmission redundancy and the incorporati on of various diversity techniques provide an RF system that is robust and
reliable under greatly varying operati onal conditi ons. Because of this inherent design, Tempest delivers superior operati onal
range and greater levels of interference and multi path fade rejecti on. Covering extremely large areas or multi ple coverage
locati ons can be problemati c with traditi onal wireless intercom systems. Tempest uti lizes diff erent roaming features that
allow it to “roam” from one coverage zone to another. When a diff erent BaseStati on is selected, the hopping patt ern and
key code of the BeltStati on is synchronized to the selected BaseStati on and the BeltStati on logs into the BaseStati on.
Audio latency is a criti cal factor in all digital systems. The hop durati on in Tempest is intenti onally kept very short - under
5ms. This short hop durati on limits the amount of data that may be lost in any one hop. More importantly, it reduces system
latency, which can cause undesirable echo. Total one-way (BeltStati on to BaseStati on) system latency is less than 50ms.
Even with this short system latency, unwanted and distracti ng echo will occur when interfacing with hardwired party-line
intercom systems unless echo-reducti on technology is implemented. Echo is primarily the result of ineffi ciencies in the
conversion of the two-wire signal. This conditi on exists in analog systems as well, but it does not cause unwanted echo
because there is no system latency delay. Tempest uses advanced echo-cancellati on algorithms to eliminate this echo.
Wireless intercom systems are oft en used in high-noise environments that require special design considerati on for eff ecti ve
operati on. Tempest operates extremely well even in very high ambient noise levels. This is primarily due to specifi c design
criteria which allow Tempest to achieve an audio dynamic range of greater than 94dB. This is more than double that of
most other digital wireless communicati on systems. This design makes Tempest ideal for use at sporti ng venues, concerts
and other events where unwanted noise levels are high.
Tempest off ers a host of features and technology to ensure that it performs well in almost all producti on environments
virtually anywhere in the world with no licensing requirements or fees.