User`s guide

5Key Reference
122 N9340B User’s Guide
Mask Fuction
Key access: [MODE] > {IBOC Measurement} > {AM}/{FM}
> {Mask Function}
Accesses the submenu to configure the mask
related settings.
•Mask Type
There are two types of mask in spectrum mask
measurement for IBOC standard: FCC spectral
emission mask and NRSC spectral emission
limits. NRSC spectral emission is leveraged from
the related specifications of iBiquity Digital
Corporation.
The mask types for IBOC- AM are listed as
below:
• FCC (AM- 73.44)
• NRSC- 5- B Hybrid 5k
• NRSC- 5- B Hybrid 8k
• NRSC- 5- B All Digital
Figure 5-30 IBOC (AM) spectral emission mask and limits
-80 -60 -4 0 -20 0 20 40 60 80
-1 10
-1 00
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
Offse t from c arrier frequ enc y (k Hz)
Level relative to unmo dulat ed carrier(dBc)
IBOC (AM) spec tral emission mask and limits
Trac e i n red is FCC spectral emission mask.
Trac e i n blue is NRSC hybrid 5 kHz spectral emissions limits.
Trac e i n magenta is NRSC hybrid 8 kHz spectral emissions limits.
Trace in Black is NRSC all digital spectral emissions limits.