Replace the polyphase filter and resampler with a separate
implementation using SSE enabled convolution. The USRP2 (including
derived devices N200, N210) are the only supported devices that
require sample rate conversion, so set the default resampling
parameters for the 100 MHz FPGA clock. This changes the previous
resampling ratios.
270.833 kHz -> 400 kHz (65 / 96)
270.833 kHz -> 390.625 kHz (52 / 75)
The new resampling factor uses a USRP resampling factor of 256
instead of 250. On the device, this allows two halfband filters to
be used rather than one. The end result is reduced distortial and
aliasing effecits from CIC filter rolloff.
B100 and USRP1 will no be supported at 400 ksps with these changes.
Signed-off-by: Thomas Tsou <tom@tsou.cc>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@6733 19bc5d8c-e614-43d4-8b26-e1612bc8e597
This large patch replaced the convolve() call with an SSE vector
enabled version. The lower C and SSE intrinsic based code operates
on fixed and aligned vectors for the filter taps. The storage format
of interleaved I/Q for both complex and real vectors is maintained.
SSE filter tap values must:
1. Start 16-byte aligned
2. Number with a multiple of 4 between 4 and 20 for real taps
3. Number with a multiple of 4 for complex taps
Non-compliant values will fall back to non-SSE usage. Fixed length
iterators mean that head and tail cases may require reallocation of
the input vector, which is automatically handled by the upper C++
interface.
Other calls are affected by these changes and adjusted or rewritten
accordingly. The underlying algorithms, however, are unchanged.
generateGSMPulse()
analyzeTrafficBurst()
detectRACHBurst()
Intel SSE configuration is automatically detected and configured at
build time with Autoconf macros.
Signed-off-by: Thomas Tsou <tom@tsou.cc>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@6732 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Remove the built time resampling selection and link both options.
Move the normal push/pullBuffer() calls back to the base class and
overload them in the inherited resampling class.
USRP2/N2xx devices are the only devices that require resampling so
return that resampling is necessary on the device open(), which is
the point at which the device type will be known.
The GSM transceiver only operates at a whole number multiple of
the GSM rate and doesn't care about the actual device rate and
if resampling is used. Therefore GSM specific portion of the
transceiver should only need to submit the samples-per-symbol
value to the device interface.
Then, the device should be able to determine the appropriate
sample rate (400 ksps or 270.833 ksps) and if resampling is
appropriate.
Signed-off-by: Thomas Tsou <tom@tsou.cc>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@6723 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Not sure why this functionality is commented out.
Make install places the FPGA firmware image in:
/usr/local/share/usrp/rev2/
/usr/local/share/usrp/rev4/
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2690 19bc5d8c-e614-43d4-8b26-e1612bc8e597
With transceiver integration, the resampling filter files were
dropped. This created a working resampling implementation for
the USRP2 / N200, but with spectrum irregulaties that likely
caused issues at longer range operation. Simply reinsert the
filter files and modify the filter initialization to use them.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2689 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Usage:
./configure --with-usrp1
Enable non-UHD USRP1 support through the gnuradio-based
driver. Requires gnuradio (libusrp) to be installed.
./configure --with-resample
Enable host-based 400ksps to 270.833ksps resampling.
Only supported for UHD devices. If not enabled, the GSM
sample rate is requested directly from the device.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2681 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Move push and pull of buffers into a dedicated file. This will
allow us to swap out resampling, non-resampling, and possibly
floating point device interfaces while presenting a single
floating point abstration in the interface itself.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2670 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Remove radio clock and vector interfaces into their own
files. This clears up and simplifies the radio interface
and, additionaly, prepares for a further split of the I/O
portion for optional resampler use.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2669 19bc5d8c-e614-43d4-8b26-e1612bc8e597
