TracVision M3 User’s Guide
6
Chapter 1 - Introduction
Linear Satellite Signals
Your TracVision system is configured to receive linearly polarized
satellite signals. Satellites around the world (with the exception of
satellites in North America, which transmit circularly polarized
signals) transmit linear signals in vertical and horizontal “waves” that
are offset exactly 90º from each other. This orientation doubles the
bandwidth, allowing the satellite to deliver hundreds of channels of
digital entertainment to your vessel.
Figure 1-2 Linearly Polarized Satellite Signals
LNB Skew Angle
Since linear satellite signals are oriented in a precise cross pattern, the
TracVision antenna’s receiving element, called an LNB (low-noise
block) must be oriented in the same way to optimize reception. This
orientation adjustment is referred to as the LNB’s “skew angle.” The
figure below illustrates how skew determines the amount of signal the
LNB collects. The more signal, the better the reception.
Figure 1-3 How Skew Works
Ideal Skew
Good Skew
Bad Skew
= Satellite Signal
= LNB "Signal Collector"
