This is machine translation

Translated by Microsoft
Mouseover text to see original. Click the button below to return to the English version of the page.

Note: This page has been translated by MathWorks. Click here to see
To view all translated materials including this page, select Country from the country navigator on the bottom of this page.

DC Blocking

Direct conversion receivers often impose a direct current (DC) bias on the in-phase and quadrature components of the signal. DC bias can degrade BER performance for QAM and PSK systems. By enabling DC blocking, you can reduce DC bias in the I/Q channels of a received complex signal. The reduced DC bias better enables robust receiver processing. In addition, this reduction enables you to focus on designing the baseband algorithm without worrying about DC bias that is introduced by the analog front end. DC blocking for the AD9361 RF chip on the USRP®[1] E310 embedded series radio hardware takes place on the RF transceiver and can be implemented at baseband or RF. For more information, see Baseband DC Offset Calibration and Baseband DC Offset Tracking in Analog Devices® AD9364 Reference Manual - UG-673.

DC Blocking on Receiver Block

DC blocking at RF and baseband is on by default. To disable these parameters, on the Advanced tab of the Receiver block mask, clear Enable RF DC tracking or Enable baseband DC tracking.

DC Blocking in Receiver System Object

DC blocking at RF and baseband is on by default. To see these properties, set the ShowAdvancedProperties property to true. To disable either of these properties, set the corresponding properties to false. For example:

rx = sdrrx('E310');
rx.EnableRFDCTracking = false;
rx.EnableBasebandDCTracking = false;

See Also



System Objects


[1] Analog Devices AD9364 Reference Manual - UG-673.

[1] USRP, USRP2, UHD, and Ettus Research are trademarks of National Instruments Corp.