ITBANDPASSCONFIG

Enable and configure bandpass filter on receiver

Platform:

OEM719, OEM729, OEM7500, OEM7600, OEM7700, OEM7720, PwrPak7, CPT7, CPT7700, SMART7

Use this command to apply a bandpass filter at a certain frequency to mitigate interference in the pass band of GNSS signals. The ITBANDPASSBANK log provides information on the allowable configuration settings for each frequency band. The bandpass filter is symmetrical in nature, which means that specifying one cutoff frequency will apply a cutoff on both the low side and high side of the signal's center frequency. Only one filter can be applied for each signal.

For dual antenna receivers, an ITBANDPASSCONFIG_1 command is used to enable a filter on the signal received from only the second antenna. An ITBANDPASSCONFIG command enables a filter on the signal received from only the primary antenna.

The ITBANDPASSCONFIG and ITBANDPASSCONFIG_1 commands use the same message ID.

On dual antenna receivers, any filter enabled for GPS L2 or GLONASS L2 on the secondary antenna will be applied to both GPS L2 and GLONASS L2. For this reason, care must be taken to avoid attenuating the signals with a bandpass filter that is too narrow in bandwidth. The recommended maximum lower cutoff frequency is 1221 MHz. The recommended minimum upper cutoff frequency is 1254 MHz.

When applying a filter to a signal using the MEC correlator, a brief interruption in tracking may occur on affected channels.

The MEC correlator is not available on firmware 7.10.xx.

This command is not available for L-band.

This command is available only on some software models. Contact your NovAtel Sales representative (novatel.com/contactus/sales-offices) to obtain interference mitigation functionality.

For more details on recommended filter placement to ensure optimal performance, refer to Table: Filter warnings and constraints.

Users can activate digital filters in either HDR or CIC3 mode. For optimal performance, HDR mode is recommended. However, HDR mode results in increased power consumption.

Message ID: 1999

Abbreviated ASCII syntax:

ITBANDPASSCONFIG frequency switch [cutofffrequency]

ASCII example:

ITBANDPASSCONFIG gpsl5 enable 1165.975

Field	Field type	ASCII value	Binary value	Description	Format	Binary bytes	Binary offset
1	Command header	-	-	ITBANDPASSCONFIG header This field contains the command name for abbreviated ASCII or the message header for ASCII or Binary.	-	H	0
2	frequency	See Table: Frequency types		Set the frequency band on which to apply the filter	Enum	4	H
3	switch	DISABLE	0	Disable filter	Enum	4	H+4
		ENABLE	1	Enable filter
4	cutofffrequency			Cut off frequency for band pass filter (MHz). (default = 0) Refer to ITBANDPASSBANK log for the allowable values.	Float	4	H+8