Manpack UHF Radios

Model, simulate and analyze the performance of a Tactical MANET radio network

  • 50 soldiers engaging the enemy, are divided into five groups with 10 in each group.
  • Soldiers in each group are continuously moving. Soldiers belonging to a group move together
  • Communication happens within the group, as well as across the group.

NetSim Simulator: Manet

NetSim Simulator: Manet
  • Technology: MANET over TDMA
  • Simulation Environment Size: 5 Km * 5 Km
  • No. of wireless nodes:50 wireless nodes in 5 groups of 10
  • Transport Layer UDP
  • Network layer DSR, AODV, ZRP, OLSR
  • Data Link Layer Dynamic TDMA
  • Physical Layer:
    • Protocol: DTDMA
    • Band: UHF
    • Frequency Range: 476 MHz to 478 MHz
    • Channel Bandwidth (MHz): 2
    • Modulation: QPSK, 16-QAM, 64-QAM
    • Transmitter power: 4W
    • Receiver sensitivity: -119 dBm
  • RF Propagation:
    • Path Loss Model: Log Distance
    • Fading Model: Rayleigh
    • Shadowing Model: Log Normal
  • Applications: Voice Applications
  • Traffic rate:
    • 9.6 Kbps voice traffic
    • Voice applications between the same group members
    • Voice applications between the members in different groups

Performance Evaluation

We conducted an analysis of Network layer protocols: AODV (Ad hoc On-Demand Distance Vector) and OLSR (Optimized Link State Routing). Our study focused on:

  • Throughput: Measuring the rate of successful data delivery.
  • Latency: Assessing the delay in data transmission.
  • Multi-hop Communication: Evaluating application performance across multiple network nodes.

These metrics were specifically examined in the context of voice applications, which have strict performance requirements.

Key Findings

Protocol Performance

  • AODV (Ad hoc On-Demand Distance Vector):
    • Exhibits lower convergence time with fewer active applications (traffic streams).
    • Performs better in non-congested network scenarios.
    • Better packet delivery rate in high mobility conditions.
  • OLSR (Optimized Link State Routing):
    • Exhibits faster convergence when handling a higher number of applications.
    • Performs better in congested network environments.
    • Better packet delivery rate in low mobility conditions.

Multi-hop Scenarios

  • In all cases, OLSR has lower latency than AODV.
  • Both protocols show a significant increase in latency beyond three hops.
  • Latency exceeds acceptable thresholds for voice communication in these cases.

Conclusions

  1. Protocol Selection:
    • AODV is preferable for networks with lighter traffic load and fewer applications (traffic streams).
    • OLSR is more suitable for networks with heavier traffic load and more number of applications.
  2. Network Design Considerations:
    • Limit the number of hops to three or fewer when designing networks for voice applications.

This analysis provided insights for network designers in optimizing protocol selection and network topology for voice applications in Military radio networks.