Standard:ITU-R 468

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ITU-R 468 is a standard relating to Noise measurement currently maintained by the European Broadcasting Union, who took it over from the CCIR.

It was previously CCIR Recommendation 468-4.

It defines a Weighting filter for use in weighted noise measurement, together with a Quasi-peak rectifier having special characteristics as defined by specified Tone-burst tests.

SUMMARY of SPECIFICATION (This is not the full definitive Standard)

Contents 1 Weighting curve specification (Weighted measurement) 2 Tone-burst response requirements 3 Repetitive tone-burst response 4 Unweighted measurement

[edit] Weighting curve specification (Weighted measurement)

31Hz -29.9dB
63 -23.9
100 -19.8
200 -13.8
400 -7.8
800 -1.9
1kHz 0.0dB
2k0 +5.6
3k15 +9.0
4k0 +10.5
5k0 +11.7
6k3 +12.2
7k1 +12.0
8k0 +11.4
9k0 +10.1
10k +8.1
12k5 0.0
14k -5.3
16k -11.7
20k -22.2
31k5 -42.7

[edit] Tone-burst response requirements

5kHz single bursts:

200ms -1.9dB
100ms -3.3
50ms -4.6
20ms -5.7
10ms -6.4
5ms -8.0
2ms -11.5
1ms -15.4

[edit] Repetitive tone-burst response

5ms 5kHz bursts at repetition rate:

2/sec -6.4dB
10/sec -2.3
100/sec -0.25

[edit] Unweighted measurement

Uses 22Hz HPF and 22kHz LPF 18dB/octave or greater (Tables to be added)