Capacity Evaluation of Frequency Hopping Based
Apurva Kumar <email@example.com>
Rajeev Gupta <firstname.lastname@example.org>
IBM India Research Lab, New Delhi, India
The IEEE 802.15 Wireless Personal Area Networks (WPAN) study
group has been working on evolving a standard for short-range
wireless connectivity between low complexity and low power
devices operating within the personal operating space (POS).
The scenarios envisioned for WPANs are likely to involve a large
number of POSs operating in an indoor environment. Among
short-range wireless technologies, BluetoothTM 1 based ad-hoc
connectivity comes closest to satisfying the WPAN requirements.
Bluetooth provides a gross rate of 1 Mbps per network and
allows several such networks to overlap using frequency hopping.
The 'aggregate throughput' thus achieved is much higher than
1 Mbps. In the absence of external interfering sources,
aggregate throughput is limited by self interference which
depends upon, (i) physical layer parameters like hopping rate,
hopping sequences, transmitted power, receiver sensitivity,
modulation, forward error correction (ii) channel characteristics
like coherence bandwidth and coherence time (iii) spatial
characteristics. In this work we consider the problem of
finding the capacity of Bluetooth based ad-hoc systems by
accurately modeling the Bluetooth physical layer and the
indoor wireless channel. We predict the throughput in Bluetooth
based ad-hoc systems as a function of a generalized set of
parameters using realistic scenarios and assumptions.