Reduce the burst detection threshold to pass more bursts to upper
layers, but force stricter requirements on the computation itself.
For the latter, we now require at least 5 samples (rather than 2)
to compute a peak-to-average value.
End result is increased burst detection at low SNR conditions with
a small increase in false positive bursts when no signal is present.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Add new radio interface "radioInterfaceMulti" for multi-carrier
support.
Only USRP B200/B210 devices are supported because of sample
rate requirements (3.2 Msps).
Only 4 SPS operation Tx/RX is supported.
8-PSK is supported.
Other options may be added at a later time
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Introduce polyphase channelizer (Rx) and synthesis (Tx) filterbanks,
which serve as the signal processing backend for multi-carrier GSM.
Fast Fourier Transform (FFT) is used internally. FFTW is added as
a new build dependency.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Two buffers, inner and outer, are used in the transceiver
implementation. The outer buffer interfaces with the device receive
interface to guarantee timestamp aligned and contiguously allocated
sample buffers. The inner buffer absorbs vector size differences between
GSM bursts (156 or 157 samples) and the resampler interface (typically
fixed multiples of 65).
Reimplement the inner buffer with a ring buffer that allows fixed size
segments on the outer (resampler) portion and variable lengths (GSM
side) on the inner side. Compared to the previous stack-like version,
this implementation removes unnecessary copying of buffer contents.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Rather than a simple bool type, convert the diversity switch
to the device interface specifer:
enum InterfaceType {
NORMAL,
RESAMP_64M,
RESAMP_100M,
DIVERSITY,
};
The more general specifier allows passing in special cases
other then selection diversity such as multi-ARFCN support.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Previous approach was to enable 4 SPS on the receive path only
for EDGE use, which is not a requirement for 4 SPS operation.
Make the 4 SPS configuration setting directly settable.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
OsmoTRX does not support the use of multiple TSC settings per
internal TRX instance. There should not be an error to modifiy
the TSC value after POWERON. Setting TSC value on TRX channels
other then 0 is a NOP operation that should only error if the
requested TSC differs from that of TRX channel 0.
Reported-by: Max <msuraev@sysmocom.de>
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Right now if you forget to send "POWER" control command, osmo-trx
will transmitt zeros. This is counter-intuitive and I've spent several
hours debugging this "issue". The issue may happen easily, because
osmo-bts doesn't send "POWER" command if there is no "power" setting
in the configuration file. Given that "POWER" command actually sets
attenuation, it's percieved as optional and in absence of it should
default to "POWER 0" (no attenuation), which translates to power
scale being 1.0.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
So we had the following define:
#define GSMRATE 1625e3/6
Now, I wanted to use it in the following expression:
3.0/GSMRATE
which turns into:
3.0/1625e3/6
while what I really wanted is:
3.0/(1625e3/6) = 3.0/1625e3*6
To avoid this, all macros with calculations must be enclosed in parentheses.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
When you build from an external path, compiler can't find convert.h
include, because it was specified relative to the current directory.
Change this to specify the include dit relative to the Makefile
location.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Slightly widen the search range to accommodate timing jitter
on certain classes of devices. The expanded range minimizes
the possibility of missing bursts that arrive too early or
too late due to timing error.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Create runtime version check for minimum supported UHD driver
when using USRP E3XX devices. The minimum version, 3.9.0, matches
supported version on current E3XX release images.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
The majority of GSM host platforms are capable of operating with
the 4x oversampled modulator, which justifies the new default
setting. The small number exceptions (e.g. Raspberry Pi) can still
use the lower complexity 1 sps modulator with the '-s 1' command
line option if required.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Tune timing values after testing on UHD 003.009.002 for E3XX.
Table value for 1 sps was off by 10 samples causing improper
operation. Table value for 4 sps was shifted by 1 sample for
more accurate timing.
Also update E3XX description string detection.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Current UDP receive reads up to MAX_UDP_LENGTH bytes into the
passed in buffer, which may lead to buffer overflow if the
write buffer is of insufficient size.
Add mandatory length argument to UDP socket receive calls.
Reported-by: Simone Margaritelli <simone@zimperium.com>
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Reported security vulnerability where control and data UDP
packets can be injected into the transceiver externally due
to socket binding to all interfaces using INADDR_ANY.
Existing socket interface does not allow specifying local
address; only the local port and remote address/port are
arguments.
Restrict socket bind to localhost with INADDR_LOOPBACK. If
external interfaces do need to be used, the API should be
modified to allow specifying the local socket address.
Reported-by: Simone Margaritelli <simone@zimperium.com>
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
EDGE 8-PSK soft slicer was receiving input from the output of the
downsampler. Equalization and derotation were missing causing the
soft symbol output to be invalid.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Delay the EDGE downlink bursts by one symbol in order to match GMSK
pulse shaping group delay. The difference in group delay arises from
the dual pulse filter combination of the GMSK Laurent represenation
whereas 8-PSK uses a single pulse linear filter.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Previously MAXDLY value was applied to Normal Bursts, which was nice
when working with sloppy test equipment like CMD57, but useless for
real world usage. At the same time documentation and de facto usage
of MAXDLY in OsmoBTS and OpenBTS assumed that it actually applies to
Access Bursts (RACH). So this patch changes osmo-rx behavior to apply
MAXDLY to RACH bursts and introduces a new command MAXDLYNB for the
old behavior.
debugLogEarly was replaced to an empty space and arguments of the function
became operators, grouped together by ():
Configuration.cpp: In member function 'bool ConfigurationTable::defines(const string&)':
Configuration.cpp:272:28: warning: left operand of comma operator has no effect [-Wunused-value]
debugLogEarly(LOG_ALERT, "configuration parameter %s not found", key.c_str());
^
This fix removes debugLogEarly together with its arguments.
Commit 871b8782 "EDGE: Add support for UmTRX" disabled B210 support
using EDGE. Add B210 explicitly to the timing offset table to avoid
this issue.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
There doesn't seem to be a reason why this shouldn't be in master.
The fairwaves/master branch is removing --march=native as well that
looks like a good idea as well.
Timing recovery and single tap channel compensation are identical
in both GMSK and EDGE receivers. This is the section ahead of and
including the optional 4-1 downsampler. GMSK and EDGE specific
sections operate at 1 SPS.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
When EDGE is enabled with the '-e' option, the random burst generator
switches from GMSK normal bursts to 8-PSK EDGE bursts.
$ ./osmo-trx -e -r 7
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Setup generators for empty, random, and dummy bursts. This moves error
prone burst length handling out of the Transceiver and into the signal
processing core.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
At 4 samples per symbol, we don't need to maintain the 156/157 sample
slot structure to account for the GSM 156.25 sample burst length.
Set the 4 SPS Laurent modulator to ignore the guard interval setting
and always output 625 sample sized bursts. The EDGE 8-PSK modulator
already has this behavior.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Create EDGE slot type in the Transceiver. When EDGE mode is enabled
for a particular slot, blind detection will be performed by
correlating against EDGE followed by normal bursts if no EDGE burst
is found.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Setup correlator and detection process similar to the GMSK
receiver chain. Require 4 SPS sampling on both Rx and Tx paths
as 1 SPS sampling adds too much distoration for 8-PSK recovery.
Core receiver operations still run at 1 SPS with the exception
of fractional delay filtering, which runs at the higher rate.
Perform linear equalization to handle the Gaussian pulse
induced ISI. The fixed impulse response used for equalizer tap
calculation consists of combined EDGE pulse shape filter and
effects of the downsampling filter. Note that the non-adaptive
equalizer corrects for modulation induced band limiting and
does not account for or compensate for fading channel effects.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Allow setting the device to non single SPS sample rates - mainly
running at 4 SPS as the signal processing library does not support
other rates. Wider bandwith support is required on the receive path
to avoid 8-PSK bandlimiting distortion for EDGE.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
DFE equalizer is unused and has been experiencing code rot for
multiple years. The effect is a significant amount of baggage being
carried in the Transceiver and interfaces.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Samples per symbol used by the transceiver is not configurable through
the socket interface once running, so stop pretending like it could be.
Initialize all tables and midambles at start.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Patch f147b174 "sigproc: Make convolution and convert input buffers
immutable" changed the internal conversion interface with the addition
of the const type qualifier. This change was not reflected on ARM builds
which led to build failure. Add const qualifier to resolve build issue.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Certain pre-release versions of the B200mini used the B205 naming, which no
longer exists. Update device naming and detection to reflect current UHD
product names.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
UHD handles built in tick and floating point timestamp conversion
since version 003.005.004. This removes the need for separate UHD
timespec to tick conversion.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Commit 90f7a01d lost "return" statement. We also should account the fact that
offset can be negative.
We should return the tuning request immediately after
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>