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2.048Mbps Wireless Modem
TECHNICAL: 0118 931 2233
Note: Installations exceeding regulations set by local authorities expose the installer and the
user to potential legal and financial liabilities.
LNA-10 Low Noise Receive Amplifier
The LNA-10 is a high-performance, low-noise preamplifier designed to enhance fringe area
reception and to provide additional gain on the receive antenna, especially when using long
cable runs. The exceptionally small size and lightweight of the LNA-10 enables it to be
directly mounted on the antenna by means of the female RF IN connector. Power is obtained
through an RG-59 coaxial cable connected to the power supply. The LNA-10 incorporates
internal lightning and voltage surge protection.
See page 105 for further information.
The LNA improves performance by improving the Noise Figure (NF) of the system, as
defined by the following formula:
LNA Improvement = NF (without LNA) / NF (with LNA) (*) Use this formula with absolute
values (not dB).
Consider the following typical configuration:
Figure 2-8. Achievable improvement through the use of LNA-10
To calculate the achievable improvement through the use of the LNA-10, use the following formulas:
NF (without LNA) = NF2 + (NF3 -1)/G2
NF (with LNA) = NF1 + (NF2 -1)/G1 + (NF3 -1)/(G1 *G2 )
Where:
NF1 = Noise Figure of LNA 10 = 1.4
