def __init__(self, bpdist=None, n=3.5, **kwargs):
"""Constructor.
:param bpdist: Breakpoint distance (in meters) [default = 5.0].
:param n: Pathloss exponent [default = 3.5].
:param kwargs: Additional keyword arguments passed to `Propagation`
constructor.
"""
cls = self.__class__
if bpdist is None: bpdist = cls.bpdist
self.bpdist = bpdist
Propagation.__init__(self, n=n, **kwargs)
def __init__(self, refdist=None, refloss=None, **kwargs):
"""Constructor.
:param refdist: Reference distance (in meters) [default = 1.0].
:param refloss: Pathloss at reference distance (in dB) [default = None].
If `refloss` is not specified, the default value of `refloss` is set to
the freespace pathloss at `refdist` with a pathloss exponent of 2.
"""
cls = self.__class__
if refdist is None: refdist = cls.refdist
if refloss is None: refloss = cls.refloss
self.refdist = refdist
self.refloss = refloss
Propagation.__init__(self, **kwargs)
def apply(self, p, u, v):
"""Apply breakpoint pathloss model.
:param p: Packet to modify.
:param u: Transmitting `ChannelInterface`.
:param v: Receiving `ChannelInterface`.
:return: Modified packet.
This method resets the 'pathloss' annotations after calling
`Propagation.apply()`.
"""
pkt = Propagation.apply(self, p, u, v)
# overwrite pathloss
dist = self.distance(u,v)
pl = self.pathloss(dist, bpdist=self.bpdist, fc=self.fc, n=self.n)
pkt.setanno('pathloss', pl)
return pkt
def __str__(self):
return Propagation.__str__(self) + \
"{bpdist: %.2f, n: %.1f, fc: %.1f GHz}"%(self.bpdist, self.n, self.fc*1e-9)
def __str__(self):
return Propagation.__str__(self) + \
"{n: %.1f, fc: %.1f GHz}"%(self.n, self.fc*1e-9)
