Compute the tilts only if raman-flag in sim_params is turned on.
Use actual input power in fiber (according to expected propagation
during design).
Creates a function that computes the expected tilt after propagation
in a span, and returns the normalized power difference at the center
frequency of each band, and the tilt experenced between lower and
upper frequency in each band.
Include the expected tilt when computing target gains of amplifiers.
Current function requires that the bands remain in the same order.
(ordering is ensured when creating the objects).
Change-Id: I28bdf13f2010153175e8b6d199fd8eea15d7b292
Introduce a design_band parameter in ROADM and Transceiver.
- if nothing is defined, use SI band(s)
- if design band is defined in ROADM, use this one for all degrees
- if per degree design band is defined, use this one instead
unsupported case: single band OMS with default multiband design band.
Check that these definitions are consistent with actual amplifiers
Signed-off-by: EstherLerouzic <esther.lerouzic@orange.com>
Change-Id: Ibea4ce6e72d2b1e96ef8cf4efaf499530d24179c
Introduce a new multi-band element that contains a list of Edfa element:
- reads multiple amps out of the element config.
- deduces frequency band from the amp in the list.
no autodesign yet: multi-band amps must have type_variety.
- checks that type variety of individual EDFAs is consistent with multiband
type variety
- demux and mux spectrum when propagate in multiband
- don't add a preamp or booster if a multiband amp is already defined.
The print of channel number is removed from equipment, since the channel number
may now depend on the path's amplifiers. This changes invocation results layout.
Signed-off-by: EstherLerouzic <esther.lerouzic@orange.com>
Change-Id: I44e77ff82e622cdee4021a7984d660317cb90cf9
The commit introduces mux/demux functions in amps and ensures that the
propagation is only done on carriers that are in the Amp bandwitdh, ie
with all their spectrum including slot width is in bandwidth.
For consistency, default amp f_min is changed:
Objective is to use amplifiers' band to bound the possible frequencies
to be propagated. Since the current default f_min of Amp in json_io.py is
higher than the SI one, this would result in a different nb of channels
than currently used in tests, and a change in all tests. In order to
avoid this, I preferred to change this value and have consistency
between SI f_min and Amp f_min.
The commits adds a set of functions to make amps band the useable
spectrum on each OMS. Thee OMS generation is changed to use the amp band.
The commit adds filtering functions (demux and mux) to filter out spectrum
which is not in the amplifier band.
Spectrum assignment is also corrected to correctly match the amp bandwidth
constraint with guardband: center frequency index must be within the
usable part of the amp band. This changes a bit the notion of freq_index
and guardband in the functions, but this is transparent to user:
f_min, f_max represent the amp band, while self.freq_index_min/max
represent the center frequency boundary for a reference 50GHz channel.
Signed-off-by: EstherLerouzic <esther.lerouzic@orange.com>
Change-Id: I225b2b2dc0e1f1992c0460f6e08fa9c9bc641edf
to be conformed with ietf + to prepare for next multiband case
Signed-off-by: EstherLerouzic <esther.lerouzic@orange.com>
Change-Id: If71857ef7dff9eaaa4c16e3837d3500bcef2fa72
The parameter was introduced in commit 9736f7c032
but the export to_json was not added.
In the next commits, it is necessary to compute Raman gain during the design
phase. The sim-params used for this computation are updated during the
design phase for speed reasons. To ensure the proper restoration of user
settings for propagation, the export must include all parameters. Therefore,
this commit adds 'computed_number_of_channels' to the JSON export. This allows
for the accurate recording of all user settings locally and enables their
restoration.
Signed-off-by: EstherLerouzic <esther.lerouzic@orange.com>
Change-Id: I221a6f614010edea9cf46c3a7d43c5be064ff09c
default parameters are shared between json and network function,
so it is better to have them on the parameters to avoid circular
dependency when importing modules
Signed-off-by: EstherLerouzic <esther.lerouzic@orange.com>
Change-Id: Ib9d41852e394586d36f74992c91f67f3330cc552
- Replaced multiple calls to the span_loss function
with recording the span loss result in the fiber elements,
reducing computation time.
- Updated Raman gain estimation based on design target powers to ensure
accurate Edfa gain calculation or gain reduction during design.
- display the computed and design Raman gain in RamanFiber string output
- do not add padding on Raman fibers
- Added to_json function to preserve user input SimParams values,
which were previously overwritten by initializing SimParams
with fake values during design.
Next step is to allow users to balance computation time and
target accuracy of the design by inputing their own SimParams
and ref channels design values.
Signed-off-by: EstherLerouzic <esther.lerouzic@orange.com>
Change-Id: I1ca4954d0621858cefb3d776a538131992cae3e3
Before the Raman coefficient was normalized with respect the given effective area, instead of the reference.
Change-Id: I4c0547db4fbd0f823a9058022b93c1ca37d67b51
- wrong parameter was used in parameter
- error message could not read 0-dimensional arrey for 0 and -1 element
- add a test that makes use of the feature
Signed-off-by: EstherLerouzic <esther.lerouzic@orange.com>
Change-Id: Id7f6d6766d5b91a4b9410ad23aaa5e472b8ebb6f
The parameters of the EDFA are explicitely retrieved in the EDFAParams class.
All the defaults are set instead in the gnpy.tool.json_io.AMP class.
Where required, the AMP.default_values are used instead of an empty dictionary.
Change-Id: Iba80a6a56bc89feb7e959b54b9bd424ec9b0bf06
Co-authored-by: Vittorio Gatto <vittoriogatto98@gmail.com>
The chromatic dispersion and dispersion slope can be provided as a single values evaluated at the fiber reference frequency or in a dictionary containing the dispersion values evaluated at multiple frequencies:
"dispersion": {"value": [], "frequency": []}
Change-Id: I81429484dd373cc49bd9baf013247782ba1912fd
The nonlinear coefficient can be expressed at the reference frequency and will be scaled in frequency using the scaling rule of the effective area
Change-Id: Id103b227472702776bda17ab0a2a120ecfbf7473
1. Effective area scaling along frequency is implemented by means of a technological model.
2. Raman gain coefficient is extended coherently, including the scaling due to the pump frequency.
Change-Id: I4e8b79697500ef0f73ba2f969713d9bdb3e9949c
Co-authored-by: Giacomo Borraccini <giacomo.borraccini@polito.it>
Fiber latency evaluated during propagation. The speed of ligth in fiber is evaluated as the vacuum speed of ligth divided by the core reflective index n1.
The latency in the transceiver is evaluated in ms.
Change-Id: I7a3638c49f346aecaf1d4897cecf96d345fdb26c
The code look as if it was trying to prevent direct instantiation of the
SimParams class. However, instance *creation* in Python is actually
handled via `__new__` which was not overridden. In addition, the
`get()` accessor was invoking `SimParams.__new__()` directly, which
meant that this class was instantiated each time it was needed.
Let's cut the boilerplate by getting rid of the extra step and just use
the regular constructor.
This patch doesn't change anything in actual observable behavior. I
still do not like this implicit singleton design pattern, but nuking
that will have to wait until some other time.
Change-Id: I3ca81bcd0042e91b4f6b7581879922611f18febe
Constant power per slot_width uses the slot width instead of
baud rate compared to PSD.
This is the equalization used in OpenROADM
add tests for constant power per slot width equalization
Signed-off-by: EstherLerouzic <esther.lerouzic@orange.com>
Change-Id: Ie350e4c15cb6b54c15e418556fe33e72486cb134
On a ROADM, the code would previously set the same per-carrier power
regardless of the channel spectrum width. With this patch, carriers are
equalized either by their:
- absolute power (same as before),
- power spectral density (PSD).
Also, it's possible to apply a per-channel power offset (in dB) which
will be applied to a specified channel on top of the selected
power-level or PSD strategy. The same offset can be also selected
through the `--spectrum` option via the `default_pdb` parameter.
The equalization policy can be set via the ROADM model (in the equipment
config) as well as on a per-instance basis.
The PSD is defined as the absolute power over a spectral bandwidth,
where the spectral bandwidth corresponds to the actual spectrum
occupation (without any applicable guard bands), as approximated by the
symbol rate. PSD is specified in mW/GHz. As an example, for a 32 GBaud
signal at 0.01 mW, the PSD is 0.01/32 = 3.125e-4 mW/GHz.
This has some implications on the power sweep and ROADM behavior. Same
as previously (with absolute power targets), the ROADM design determines
the power set points. Target power is usually the best (highest) power
that can be supported by the ROADMs, especially the Add/Drop and express
stages' losses, with the goal to maximize the power at the booster's
input. As such, the `--power` option (or the power sweep) doesn't
manipulate with ROADM's target output power, but only with the output
power of the amplifiers. With PSD equalization, the `--power` option is
interpreted as the power of the reference channel defined in equipment
config's `SI` container, and its PSD is used for propagation. Power
sweep is interpreted in the same way, e.g.:
"SI":[{
"f_min": 191.3e12,
"baud_rate": 32e9,
"f_max":195.1e12,
"spacing": 50e9,
"power_dbm": 0,
"power_range_db": [-1,1,1],
"roll_off": 0.15,
"tx_osnr": 40,
"sys_margins": 2
}],
...and with the PSD equalization in a ROADM:
{
"uid": "roadm A",
"type": "Roadm",
"params": {
"target_psd_out_mWperGHz": 3.125e-4,
}
},
{
"uid": "edfa in roadm A to toto",
"type": "Edfa",
"type_variety": "standard_medium_gain",
"operational": {
"gain_target": 22,
"delta_p": 2,
"tilt_target": 0.0,
"out_voa": 0
}
},
then we use the power steps of the power_range_db to compute resulting
powers of each carrier out of the booster amp:
power_db = psd2powerdbm(target_psd_out_mWperGHz, baud_rate)
sweep = power_db + delta_power for delta_power in power_range_db
Assuming one 32Gbaud and one 64Gbaud carriers:
32 Gbaud 64 Gbaud
roadmA out power
(sig+ase+nli) -20dBm -17dBm
EDFA out power
range[
-1 1dBm 4dBm
0 2dBm 5dBm
1 3dBm 6dBm
]
Design case:
Design is performed based on the reference channel set defined in SI
in equipment config (independantly of equalization process):
"SI":[{
"f_min": 191.3e12,
"baud_rate": 32e9,
"f_max":195.1e12,
"spacing": 50e9,
"power_dbm": -1,
"power_range_db": [0,0,1],
"roll_off": 0.15,
"tx_osnr": 40,
"sys_margins": 2
}],
`delta_p` values of amps refer to this reference channel, but are applicable
for any baudrate during propagation, e.g.:
{
"uid": "roadm A",
"type": "Roadm",
"params": {
"target_psd_out_mWperGHz": 2.717e-4,
}
},
{
"uid": "edfa in roadm A to toto",
"type": "Edfa",
"type_variety": "standard_medium_gain",
"operational": {
"gain_target": 22,
"delta_p": 2,
"tilt_target": 0.0,
"out_voa": 0
}
},
Then the output power for a 64 Gbaud carrier will be +4 =
= lin2db(db2lin(power_dbm + delta_p)/32e9 * 64e9)
= lin2db(db2lin(power_dbm + delta_p) * 2)
= powerdbm + delta + 3 = 4 dBm
Signed-off-by: EstherLerouzic <esther.lerouzic@orange.com>
Change-Id: I28bcfeb72b0e74380b087762bb92ba5d39219eb3
The lumped losses are used in the computation of the loss/gain profile
through the fiber whether the Raman effect is considered or not. The
computed power profile is used to calculate the related NLI impairment.
Using the 'gn_model_analytic' method, the lumped losses are taken into
account as the contribution of an additional total loss at the end of
the fiber span. In case the 'ggn_spectrally_separated' is selected, the
method uses the computed power profile according to the specified z and
frequency arrays. The lumped losses are so considered within the NLI
power evolution along the fiber.
Change-Id: I73a6baa321aca4d041cafa180f47afed824ce267
Signed-off-by: Jan Kundrát <jan.kundrat@telecominfraproject.com>
In this change, the RamanSolver is completely restructured in order to obtain a simplified and faster solution of the Raman equation. Additionally, the inter-channel Raman effect can be evaluated also in the standard fiber, when no Raman pumping is present. The same is true for the GGN model.
The Raman pump parameter pumps_loss_coef has been removed as it was not used. The loss coefficient value evaluated at the pump frequency can be included within the fiber loss_coef parameter.
This change induces variations in some expected test results as the Raman profile solution is calculated by a completely distinct algorithm. Nevertheless, these variations are negligible being lower than 0.1dB.
Change-Id: Iaa40fbb23c555571497e1ff3bf19dbcbfcadf96b
Gamma and the raman efficiency are calculated using the effective area if not provided. Both these parameters are managed as optional in json_io.py for backward compatibility.
Change-Id: Id7f1403ae33aeeff7ec464e4c7f9c1dcfa946827
Modification of the Fiber and the NliSolver in order to properly propagate the new definition of the spectral information taking advantage of the numpy array structures.
In the previous version, the propagation of the spectral information was implemented by means of for cycles over each channel, in turn.
In this change the propagation is applied directly on the newly defined spectral information attributes as numpy arrays.
Additional changes:
- Simplification of the FiberParameters and the NliParameters;
- Previous issues regarding the loss_coef definition along the frequency are solved;
- New test in test_science_utils.py verifing that the fiber propagation provides the correct values in case of a few cases of flex grid spectra.
Change-Id: Id71f36effba35fc3ed4bbf2481a3cf6566ccb51c
Squeeze function has been replaced by asarray. Using 'get' function
instead of if condition for the dictionaries. Frequency reference
derived from wavelength reference of 1550 nm.
Change-Id: I815ad8591c9e238f3fc9322ca0946ea469ff448f
This change siplifies the structure of the simulation parameters,
removing the gnpy.science_utils.simulation layer, provides some
documentation of the parameters and define a mock fixture for testing in
safe mode.
Jan: while I'm not thrilled by this concept of hidden global state, we
agreed to let it in as a temporary measure (so as not to hold merging of
Andrea's flexgrid/multirate patches). I've refactored this to a more
pytest-ish way of dealing with fixtures. In the end, it was also
possible to remove the MockSimParams class because it was not adding any
features on top of what SimParams can do already (and to what was
tested).
Change-Id: If5ef341e0585586127d5dae3f39dca2c232236f1
Signed-off-by: Jan Kundrát <jan.kundrat@telecominfraproject.com>
Getter and setter removed from the class PumpParams. The propagation
direction is cast to lower case string within the PumpParams
constructor.
Change-Id: Ice28affe8bcffbf8adcebb5cb096be8100081511
The actual conversion formula includes the minus (-), not the absolute
value. We never noticed it as GNPy simulates only modern networks
based on uncompensated transmission which have not DCUs. In this case,
the sign of beta2 along a path is the same for all the spans and,
in this case, the actual amount of NLI does not change.
Change-Id: I60a61d00c578a1a0436231a2bda8e3b6256fc8b3
The TL;DR behind this patch is that it's better to have a utility
conversion function instead of having multiplier LUT and open code which
implements the conversion.
The FiberParams handling looked fishy -- apparently, it was keeping the
multiplier around, but it was unconditionally setting the units to
meters, anyway. Given that the units were not being preserved anyway
(everything got converted to meters), and that the multipler was not
used anywhere, let's refactor the code to just convert to meters using
our new utility function, and remove the unused argument.
Change-Id: Id886d409a4046f980eed569265baefd97db841bd
Apparently it's sometimes not obvious where the input data come from
(see next commit), so let's show the data which caused this excpetion to
the user.
Change-Id: Id333903a0549c4ef5dc37c2f6ff340bd357279ea
Also make sure that all modules are covered. It seems that there's no
automatic way for doing this, aargh. On the other hand, there's
apparently no need to repeat all the Sphinx markup blurb, and even
sectioning works nicely (read, "as I expect it to work") now :). I think
that it's still necessary to keep these "intermediate files" that only
trigger package-level and module-level autodocs, but hey, I can live
with this.
Change-Id: I705e0054cd7cd4350171770795d69f5c15c226d6