From 412a7053cc0698fd8e1a09d9c40ec2f96cf629af Mon Sep 17 00:00:00 2001 From: Tom Tsou Date: Wed, 28 Jun 2017 18:02:56 -0700 Subject: ad9361: Reconfigure Rx HB filters with MCR >58 MHz Disable halfband HB3 (shortest and closest filter to the ADC) and enable HB2 (larger and second closest filter to the ADC). This significantly reduces HB excess bandwidth rolloff and reduces the effective noise floor by ~20 dB at rates above 58 MHz. The filter change has no effect at clock rates below 58 MHz. Fixes #1542 "Significant raise in noise floor using MCR above 58MHz" --- host/lib/usrp/common/ad9361_driver/ad9361_device.cpp | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'host') diff --git a/host/lib/usrp/common/ad9361_driver/ad9361_device.cpp b/host/lib/usrp/common/ad9361_driver/ad9361_device.cpp index da0ab0b9a..bed13fd05 100644 --- a/host/lib/usrp/common/ad9361_driver/ad9361_device.cpp +++ b/host/lib/usrp/common/ad9361_driver/ad9361_device.cpp @@ -1454,7 +1454,8 @@ double ad9361_device_t::_setup_rates(const double rate) _rfir_factor = 2; } else if ((rate > 58e6) && (rate <= 61.44e6)) { // RX1 + RX2 enabled, 2, 1, 2, 2 - _regs.rxfilt = B8(11010110); + _regs.rxfilt = B8(11001110); + // TX1 + TX2 enabled, 2, 1, 1, 2 _regs.txfilt = B8(11010010); -- cgit v1.2.3