Operation Manual Part 2

Digital Liquid Cooled UHF
TV Equipment
Description / Test points / Location of units
9946 V1
45321648.01 104 A E
preliminary
47 / 131
Numéro / Number Doc. Rev. Lan
g
u.
16/06/2006
Pa
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e
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3.2.6. Adaptive non linear pre-correction
The adaptive precorrection algorithm computes automatically the amplitude distribution from the non
linear feedback input. Both “one shot” and “adaptive” mechanisms are available. In adaptive mode,
when shoulders after power amplification are above a threshold, the exciter computes new set of
coefficients. This system allows the best optimisation of the shoulder and MER after the transmitter
(estimated to be 1dB better than manual adjustment). Moreover, the algorithm balances the shoulder
to have the best output performance.