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Kategorie: Diplomové, bakalářské práce |
Tento dokument chci!
Tato práce zkoumá vhodnost a požadavky návrhu simulací pro simulátor NS-3 pro případ bezdrátových sítí používaných v měřící infrastruktuře společnosti Kamstrup. V práci jepopsán simulátor NS-3 a je vytvořena základní implementace dvou protokolů. WirelessM-Bus jako příklad jednosměrného protokolu pro zařízení napájené z baterií. Simulace Wireless M-Bus je porovnána s daty naměřenými v reálném systému. NS-3 poskytuje flexibilní prostředí pro vývoj simulací různých síťových protokolů, včetně těch určených pro sítě inteligentních měřidel.
Therefore the SwNetDevice
and SwMac classes described below are mostly kept for structure and are just passing
the packets the next layer. One instance this
class shared between all the devices and responsible for dispatching the received
data all listening devices’ SwPhy objects.
In the lower layers, the key events are scheduled the Channel instance:
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. Moreover, keeps pointers those objects and the Node object, which
can useful for example retrieve the node’s coordinates from lower layers, or
conversely, retrieve pointer node’s lower layer given pointer the Node
object.
Net Device
A modified SwNetDevice class, subclass NetDevice, from the Simple Wireless
module used.1).
There are SwPhy and SwMac classes. Both them are used each node.
Channel
The Channel class has been subclassed into SwChannel class. Most their original functionality (used
in the Simple Wireless Module) was removed, the WM-Bus protocol much
simpler. The SwMac forwards the data and kept in
case MAC layer model desired the future.
Events
As the NS-3 simulator event based, necessary implement the whole com-
munication set events. While generating the first message, event for the next message is
scheduled with the delay defined equation (3.
The first message device generated certain start time, that either
predefined randomly chosen from predefined range delays (with uniform
probability). The SwPhy commmunicates directly
with the Channel object, forwards the data and most importantly, checks the power
thresholds, sensitivity and SINR limits. Each message event schedules
the following message the appropriate time. forwards the packets from the MbusApp objects the SwMac
objects.Given the relative simplicity the WM-Bus protocol, all the protocol-specific
functionality has been implemented the MbusApp class. also calculates the interference levels
for each device. the Application part the simulation, the key
events are the generation messages and triggering the alarm.
The alarm events are scheduled similar way, their delays are exponentially
distributed with configurable mean value
