diff options
author | Thomas Tsou <tom@tsou.cc> | 2013-10-11 13:49:55 -0400 |
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committer | Thomas Tsou <tom@tsou.cc> | 2013-10-18 13:10:17 -0400 |
commit | c1f7c42a33a1125f8b39f53a1b6e1bae38376857 (patch) | |
tree | fd79543a262281b4cbf04bfb09f305b95a715dd4 /Transceiver52M/USRPDevice.h | |
parent | 2c282f5e1268146761413a145fd8ae2fb523fa4f (diff) |
Transceiver52M: Setup dual sample rate transceiver
This patch applies oversampling, when selected with 4 sps,
to the downlink only, while running the receiver with
minimal sampling at 1 sps. These split sample rates allow
us to run a highly accurate downlink signal with minimal
distortion, while keeping receive path channel filtering
on the FPGA.
Without this patch, we oversample the receive path and
require a steep receive filter to get similar adjacent
channel suppression as the FPGA halfband / CIC filter
combination, which comes with a high computational cost.
Signed-off-by: Thomas Tsou <tom@tsou.cc>
Diffstat (limited to 'Transceiver52M/USRPDevice.h')
-rw-r--r-- | Transceiver52M/USRPDevice.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/Transceiver52M/USRPDevice.h b/Transceiver52M/USRPDevice.h index f5bc939..01cf261 100644 --- a/Transceiver52M/USRPDevice.h +++ b/Transceiver52M/USRPDevice.h @@ -60,6 +60,7 @@ private: usrp_subdev_spec rxSubdevSpec; usrp_subdev_spec txSubdevSpec; + int sps; double actualSampleRate; ///< the actual USRP sampling rate unsigned int decimRate; ///< the USRP decimation rate @@ -87,7 +88,8 @@ private: TIMESTAMP timestampOffset; ///< timestamp offset b/w Tx and Rx blocks TIMESTAMP latestWriteTimestamp; ///< timestamp of most recent ping command TIMESTAMP pingTimestamp; ///< timestamp of most recent ping response - static const TIMESTAMP PINGOFFSET = 272; ///< undetermined delay b/w ping response timestamp and true receive timestamp + + long long pingOffset; unsigned long hi32Timestamp; unsigned long lastPktTimestamp; |