This patch is long overdue and can now be merged after better understanding
of timestamp stability issues. UHD tick / timespec conversions were
generally used with the streamer interface, though these calls are actually
independent change sets. The combination would lead to internal rounding
errors and a timing drift most notably on B100 running at GSM symbol
rate multiples. There are no known issues, however, with the streamer code
itself.
The aforementioned issue was discovered in test code only, which was never
merged to mainline.
Signed-off-by: Thomas Tsou <tom@tsou.cc>
The correlation starting point for normal burst training sequence
calculation should be a scaled value of the same symbol regardless
of the samples-per-symbol used. Use of 2 samples-per-symbols double
the index values, but yields the following outputs, which results
in a late time-of-arrival value at the output of the correlation.
This patch modifies the parameter calculation accordingly.
1 sps parameters
maxTOA = 3
spanTOA = 5;
startIx = 61;
endIx = 87;
windowLen = 26;
corrLen = 7;
2 sps parameters (errant case)
maxTOA = 6;
spanTOA = 10;
startIx = 112;
endIx = 184;
windowLen = 72;
corrLen =13;
2 sps parameters (corrected)
maxTOA = 6;
spanTOA = 10;
startIx = 122;
endIx = 174;
windowLen = 52;
corrLen =13;
Signed-off-by: Thomas Tsou <tom@tsou.cc>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@5183 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Although currently unsupported in GSM core, enable TCH/H
support in Transceiver52M for testing and future availability.
Signed-off-by: Thomas Tsou <tom@tsou.cc>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@5169 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Without this patch, if SAMPSPERSYM is set bigger than 1, then
erratic behaviour will occur.
Signed-off-by: Thomas Tsou <tom@tsou.cc>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@4633 19bc5d8c-e614-43d4-8b26-e1612bc8e597
The adaptive energy detection threshold does not scale relative
to signal level. In other words, the adjustment factor will be
the same whether the at 40% of signal level or 4%. If the receive
gain is reduced by a large amount, suppose 20 dB, the receiver
may take minutes to adjust to the new level.
When the receive gain is changed, reset the threshold back to
the initial level. This reduces issues of runtime gain adjustment
and prevents blocking bursts while the threhold level slowly
adjusts.
Signed-off-by: Thomas Tsou <tom@tsou.cc>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@4595 19bc5d8c-e614-43d4-8b26-e1612bc8e597
1)I did an experiment and compiled OpenBTS with clang yesterday, which
immediately highlighted two potential bugs in the Transceiver52 code.
I'm not sure they are indeed bugs and not the intended behavior, but
they look very much like that. The first one is below and the second
one is in the following mail.
GSM::Time() arguments are defined like #define USB_LATENCY_INTRVL
(10,0), which means that they are expanded into GSM::Time((10,0)).
This expression is a GSM::Time() with a single parameter where (10,0)
return value of the last argument, 0 in this case. I.e.
GSM::Time((10,0)) is equivalent to GSM::Time(0). I think this was not
the intention.
2) Printing \n after every complex number breaks output when you want to
print it in a single line, e.g. in many debug output.
I do not claim any copyright over this change, as it's very basic.
Looking forward to see it merged into mainline.
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@4515 19bc5d8c-e614-43d4-8b26-e1612bc8e597
UHD accepts optional 'args' that can be used for device descriptions
such as IP address, device type, etc. Allow these to be passed in on
the transceiver command line as the third argument (number of supported
carriers is the second argument). This option benefits those who may
have multiple UHD devices attached to a single system.
This option is not yet supported by GSM core and requires starting the
transceiver independently on the command line. This option has no
effect when USRP1 is used.
Signed-off-by: Thomas Tsou <tom@tsou.cc>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@4315 19bc5d8c-e614-43d4-8b26-e1612bc8e597
The appearance of underruns on B100 due to the latency transmit
window scares people. These should not be logged at ERROR level
because the events are generally not real errors. So use the same
behaviour of USRP1 of not logging these events. The presence of
underrun events can be determined by changes in the latency window
that is shown with log level set at INFO.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@3988 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Allowing the underrun flag to reset will prevent a single event from
causing large jumps in the transmit latency threshold. This should
keep unreasonable timing latencies from occurring (e.g. latencies of
20+ frames).
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@3981 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Put a floor on the transmit latency of the B100 in order to suppress
underruns in typical conditions. Empirical data from a handful of
relatively recent machines shows that the B100 will underrun when
the transmit threshold is reduced to a time of 6 and a half frames,
so we set a minimum 7 frame threshold.
The overall benefit should be marginal and may increase the
possibility of bursts arriving stale (after the trasmit deadline),
but will reduce the number of alarming UHD related messages that
appear in the log file.
This patch is UHD and B100 specific - USRP1 is unaffected.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@3980 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Transmit gain setting would deceptively set the receive
gain instead. Since transmit attenuation is a combination
of RF gain and digital scaling, this major copy/paste bug
may have gone unnoticed by many users.
Reported-by: Robin Coxe <coxe@close-haul.com>
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@3309 19bc5d8c-e614-43d4-8b26-e1612bc8e597
The "Loss of monotonic time" error occurs when a timestamp
arrives from the device that is earlier in time than the
previous timestamp. The output is an ALERT level message
generally accompanied by a transmit side timeout from the
device.
UHD: Loss of monotonic time
UHD: Loss of monotonic time
UHD: Device send timed out
Add to the error description the timestamp values that
generated the error and output with ALERT rather than
ERR log.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@3307 19bc5d8c-e614-43d4-8b26-e1612bc8e597
The failure "UHD make failed" implies that a suitable device
was found, but construction failed. Output the the found
target device information along with message.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@3181 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Unrecoverable device errors include send and receive
timeouts and mangled packets. Other device errors, such
as non-monotonic timestamps are sometimes recoverable
through a soft restart.
These fatal are generally limited to development
versions of UHD driver or device firmware, but can occur
in release versions.
Alert user on such device errors along with current UHD
version.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@3012 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Device errors regarding properties such as sample
rate or frequency tuning are almost always fatal and
lead to the common error "assuming TRX is dead".
Make sure that these errors are clearly presented to
the user.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2700 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Perform a UHD device search before constructing the object,
and inform the user if no device is found.
No device found is the most common reason for the transceiver
to fail with the dreaded error "assuming TRX is dead".
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2699 19bc5d8c-e614-43d4-8b26-e1612bc8e597
This configuration is invalid because of FPGA based timestamp
support for the USRP1 in the UHD driver.
Kindly inform the user to recompile with libusrp support from
GNU Radio.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2698 19bc5d8c-e614-43d4-8b26-e1612bc8e597
Before setting the master clock rate, make sure that the
device is capable of being set. For now, assume that devices
that operate with default clock rates above 64 MHz,
specifically USRP2/N200/N210, cannot be set at 52 MHz.
Inform the user that these devices can be used with the
compile time option of host based resampling.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2697 19bc5d8c-e614-43d4-8b26-e1612bc8e597
It was possible to reach a state where a resampled burst would
overrun the transmit output buffer and corrupt the global
allocated signal vectors. The result was a segmentation fault
when attempting to access heap allocated signal vectors since
the pointers were garbage.
Whether the segfault occured or not appears to depend on the
memory location of the signal vector pointers, since it does
not occur on all systems.
Double buffer size to accomodate an incoming burst plus up to
a full chunk that may be remaining from the previous resampling
operation.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2691 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
The following option selects single daughterboard use on
side A only. Otherwise, the default setting is TX on A and
Rx on B.
./configure --with-singledb
Other options are possible, as per the following enum, but
for simplicity with configure options, there are only two
choices.
enum dboardConfigType {
TXA_RXB,
TXB_RXA,
TXA_RXA,
TXB_RXB
};
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2687 19bc5d8c-e614-43d4-8b26-e1612bc8e597
External reference selection was already compile-time
determined by a hard coded value. Make it selectable
as a configure option.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2686 19bc5d8c-e614-43d4-8b26-e1612bc8e597
For network based devices (USRP2, N200, etc.), increase the
latency from 2 to 3 frames, which effectively buffers more
samples on the host in front of the Ethernet interface.
USB devices (USRP1 and B100) utilize an adaptive mechanism
so they are less effected by this value.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2685 19bc5d8c-e614-43d4-8b26-e1612bc8e597
The low-level RadioDevice interface is agnostic to libusrp
or uhd based devices. 'make' allocates and returns a
pointer to a generic RadioDevice implemented for whatever
class of device determined at compile time.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2684 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
With the introduction of the B100, there is USB support
using UHD devices. The characteristics of the trasmit
side burst submissions are more reflective of the bus
type than the device or driver.
Use a fixed latency interval for network devices and the
adaptive underrun approach for USB devices - regardless
of driver or device type.
The GPMC based transport on the E100 appears unaffected
by either latency scheme, which defaults to network.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2677 19bc5d8c-e614-43d4-8b26-e1612bc8e597
The resampling transceiver is unified with the 52MHz
version. The option to resample 400ksps from the device
to a GSM appropriate 270.833ksps is enabled at compile
time with the following option.
./configure --with-resamp
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2672 19bc5d8c-e614-43d4-8b26-e1612bc8e597
The readSamples call does not return less than the
number of samples requested. Doing otherwise is a
fatal error. So on overruns, which are not fatal,
continue reading until the requested number of
samples is received.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2671 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
Thomas Tsou