Vemco VR100 - Page 90

VEMCO – VR100 Manual 28 May 2018 84
Decibel (dB): A decibel is a logarithmic unit used for measuring the strength of a signal. A decibel is one
tenth of a "bel".
Detection Parameters: The detection parameter determines what is identified as a received ping and what
is considered background noise (see section 6.4).
Pinger: A VEMCO tag that contains no sensors. It can have either a coded or continuous transmission
schedule.
Position dilution of precision (PDOP): PDOP is a unitless measure that indicates when satellite
geometry will provide the most accurate results. A low PDOP indicates the satellites are nicely
arranged to give a good position. The PDOP may be improved by facing the VR100 GPS antenna
towards the equator where more satellites are located.
Pulse Position Modulation (PPM): PPM is a signal modulation technique that allows computers to share
data by measuring the time each data packet takes to reach the computer (transmitter to receiver).
Tag: A VEMCO tag is an acoustic transmitter that is attached to a marine creature and transmits an acoustic
signal. The acoustic signal is received by a VEMCO receiver. VEMCO tags can transmit either a
coded or continuous signal, with or without sensor data. After a tag is powered, it will continue to
broadcast according to factory setup until powered down.
Sensor transmitter: A VEMCO tag that has at least one sensor. The type of sensor is usually included in
the transmitter’s name. For example, a V16P has a pressure (depth) sensor and the V16T has a
temperature sensor. A sensor transmitter can also have either a coded or continuous transmission
schedule.