For VNA (for example E5071C), kinds of IFBWs can be set to balance the measure time and dynamical range. while IFBW is small, the IF filter should be very high order for IF receiver, how it is designed in VNA?
i checked the E5071C spec, while the IFBW is bigger than 100KHz, the measure time keeps constant, since 100KHz IFBW can obtain more dynamical range compared with 500KHz or 1.5MHz, why E5071C need support 500KHz and 1.5MHz?
My another question is why the measure time doesn't become shorter as IFBW bigger (>= 100KHz)?
Can anyone help explain on these topic? Thanks very much in advance.