Tait TB8100, User Manual

Page: 122 / 254

112 Part F: Configuring Channels
© Tait Electronics Limited December 2007
RSSI Gating
(carrier)
Enables gating based on the base station’s measurement of the received signal
strength. This is also known as Carrier gating. This method is not
recommended for low signal levels. If the level is set low (for example -118
dBm) and the hysteresis is set to High, the gate may stay open permanently.
SINAD Gating
(noise) Enables gating based on the ratio of signal to noise and distortion. This is also
known as noise gating.
Level The two Level boxes define the level (of RSSI or SINAD) required to unmute
the receiver and pass the received audio. Even if RSSI gating is disabled, the
RSSI level is used in power saving to quickly detect whether signal is present.
See the Installation and Operation manual for more details.
Hysteresis
The two Hysteresis boxes specify how far the RSSI or SINAD must fall below
the level set in the corresponding Level box to mute the received audio.
The Hysteresis box for RSSI gating provides the options Low, Medium, and
High. Typically, these options correspond to hysteresis values of 1–2, 2–5, and
5–10 dB respectively. The actual hysteresis varies with the RSSI gating level
(see below).
Set the hysteresis level you want, test TB8100 operation, and adjust the setting
as appropriate.
Note:
SINAD dB hysteresis is a recovered audio level measurement.
It does not correlate to RF dBm levels.
Table 1: Typical hysteresis values for the different hysteresis options
Gating Level Low Medium High
-119 dBm 0.8 3.5 5
-118 dBm 1.1 3.4 5.9
-117 dBm 1.3 3.8 5.4
-116 dBm 1.9 3.9 6
-115 dBm 2.2 4.7 6.4
-114 dBm 2.4 4.7 6.4
-110 dBm 2.9 5.6 7.4
-105 dBm 3.4 6.1 8.1
-100 dBm 3.8 6.8 8.7
-95 dBm 4.1 6.8 8.6
-90 dBm 4.7 7 9.2