R&S FSV-K70, Руководство пользователя

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Brief Description of Vector Signal Analysis
R&S
®
FSV-K70
64 Operating Manual 1176.7578.02 ─ 09
operation is optionally (de-) activated based on the corresponding user settings (see
"Measurement Filter" on page 174 ).
For the estimation of the magnitude parameters, the following least-squares criterion is
minimized:
   

  
  
n
T n
MEAS MAG
E
e K n A K C
2
,


with respect to the model parameters K and
⍺
, where T
E
denotes the sampling period
used for estimation (see "Estimation Points/Sym" on page 172).
For estimation of the frequency parameters, the following least-squares criterion is
minimized:
       
2
0 0
; , , ,

      
n
E d REF MEAS d FREQ
T n f f n f B n f f f B C
 
with respect to the model parameters B , f
0
, f
d
and
τ
. The term denotes the reference
instantaneous frequency with a (possibly fractional) delay of samples.
For FSK modulation the default sampling period used for estimation is the capture
sampling period.
2.5.2.3 Modulation Errors
A 2FSK signal is generated using a GMSK frequency pulse. Examples of carrier drift
and reference deviation are shown in
Figure 2-58 and Figure 2-59 respectively.
Carrier frequency drift
A carrier frequency drift is modeled as a linear change in the carrier frequency with
respect to time. The effect of carrier drift on the instantaneous frequency of an FSK
signal is illustrated in
Figure 2-58 .
Signal Model, Estimation and Modulation Errors