Biomedical Engineering Reference
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Fig. 2 The IEEE802.15.6
standard physical layer
protocol data unit (PPDU) for
impulse radio ultra-wideband
(IR-UWB) physical layer
(PHY) specifications
The synchronization header (SHR) provides a preamble bit pattern ( Kasami se-
quence with a length of 63) which is essential part in the narrow pulse-based UWB
data transmission. The PHY header (PHR) provides 24 data fields which are used
to indicate communication parameters such as data rate, MAC frame body length,
pulse type (chirp pulse, chaotic pulse and short pulse) and modulation mode. The
IEEE802.15.6 standard also supports bit interleaving using a modulus interleaver in
order to provide robust data transmission by avoiding large sequences of consecutive
ones and zeros. Because of the difficulty in CCA for UWB, a random access mech-
anism based on the slotted ALOHA or a polling-based medium access mechanism
is recommended for UWB-based WBANS in the IEEE802.15.6 standard.
Drawbacks: Although the IEEE802.15.6 standard defines a robust standard for
WBAN applications, it has several drawbacks when it comes to using UWB for
WBAN applications. It ignores several key limitations in the implementation of the
UWB transceivers. The MAC protocol defined by the IEEE802.15.6 standard as-
sumes the use of a UWB transceiver at the sensor node end. Although the UWB
transmitters are relatively less complex, the implementation of the UWB receiver
involves power hungry complex hardware designing (refer Sect. “ Introduction to
Ultra-Wideband-Based Wireless Body Area Networks”). Also, it ignores the opti-
mization of the UWB transmit power control through duty cycling and gated pulse
transmission techniques [ 21 , 22 ], which can be used to optimize the power consump-
tion of the transmitter node while controlling the transmit power of the sensor nodes
according to the Federal Communications Commission (FCC) regulations for UWB
transmission [ 4 ].
The IEEE802.15.4a Standard
The IEEE802.15.4a standard [ 23 ] is currently the most discussed and adopted stan-
dard for UWB applications in the literature. The IEEE802.15.4a standard has been
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