Advisory
November 1998
T7234, T7237, and T7256
Compliance with the New ETSI PSD Requirement
(Refer to the T7234, T7237, and T7256 ISDN transceiver data sheets.)
Telecommunication Standard
The European Telecommunications Standards Institute (ETSI) has identified a change in the requirement of
the power spectral density (PSD) for Basic Rate Interface ISDN.
Section A.12.4, Power Spectral Density, of ETSI TS080 states the following:
s
The upper boundary of the power spectral density of the transmitted signal shall be as shown in Figure 1,
below.
Measurements to verify compliance with this requirement are to use a noise power bandwidth of 1.0 kHz.
Systems deployed before January 1, 2000 do not have to meet this PSD requirement but shall meet the PSD
requirements as defined in ETR 080 edition 2. It is, however, expected that these systems will also meet the
PSD requirements of TS080 edition 3. Some narrowband violations could occur and should be tolerated.
s
s
–20
–30
–40
–50
PSD (dBm/Hz)
–60
–70
–80
–90
–100
–110
–120
–130
–140
0.001
0.010
0.050
1.000
0.315
30.000
5.000
0.100
f (MHz)
1.000
10.000
100.000
5-7388F
Figure 1. Upper Boundary of Power Spectral Density from NT1 and LT
The existing SCNT1 family (T7234A, T7237A, and T7256A) of U-interface transceivers fully comply with this
standard.
Conformance to the above requirement has been fully verified, and test reports are available upon request.
AGERE [ AGERE SYSTEMS ]
