Page 200 - From Smart Grid to Internet of Energy

176 From smart grid to internet of energy

FIG. 5.1 Comparison of emerging wireless communication technologies.

the 802.15.1 specification as the standard of Bluetooth in 2002. The PHY and
MAC layers of seven-layer Open Systems Interconnection (OSI) model are
characterized by the standard to ensure wireless communication with low power
consumption. The technology is principally developed for providing wireless
data transfer over short ranges. Bluetooth technology serves on the industrial,
scientific and medical (ISM) band (in 2400–2480 MHz) by utilizing frequency
hopping spread spectrum (FHSS) method and it transmits data by dividing into
the packets. The early versions of the technology provided 1 Mbps data rate
whereas Bluetooth 3.0/high-speed version (Bluetooth 3.0 + HS) theoretically
presented data transfer speed up to 24 Mbps. Two different topologies are
employed in the technology that are called as Piconet and Scatternet. Wireless
Personal Area Network (WPAN) may typically form a Piconet where one
mobile device behaves as a master and the other devices act as the slaves. A
Scatternet scheme is composed of two or more Piconets. On the other hand,
a master that manages the packet exchange process by generating clocks can
connect up to seven slaves in a Piconet topology to enable communications
among the master and slaves. A device can change its master/slave status if
the device has a requirement to join more than one Piconet.
An improved version of the technology called as Bluetooth Low Energy
(BLE) or Bluetooth 4.0 has been presented with the aim of providing lower-power
consumption and lower-latency features while protecting communication range.