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Introduction
Wi-Fi (IEEE-802.11b) and Wi-Max (IEEE-802.16e) have captured our attention. As there is
no recent developments which transfer data at faster rate, as video information transfer taking lot
of time.
This leads to introduction of Gi-Fi technology .it offers some advantages over Wi-Fi, a
similar wireless technology. In that it offers faster information rate in Gbps, less power
consumption and low cost for short range transmissions.
Gi-Fi which is developed on a integrated wireless transceiver chip. In which a small antenna
used and both transmitter- receiver integrated on a single chip which is fabricated using the
complementary metal oxide semiconductor (CMOS) process. Because of Gi-Fi transfer of large
videos, files will be within seconds
1.1 Why Gi-Fi?
The reason for pushing into Gi-Fi technology is because of slow rate, high power consumption,
low range of frequency operations of earlier technologies i.e. Bluetooth and Wi-Fi, see the
comparisons and features of those two technologies.
1.3 Disadvantages of Bluetooth and Wi-Fi:
From the table we can conclude that the bit rate of Bluetooth is 800Kbps and Wi-Fi has 11Mbps.
Both are having power consumptions 5mw and 10mw. They have lower frequency of operation
2.4GHz. For transferring large amount of videos, audios, data files take hours of time. So to have
higher data transfer rate at lower power consumption we move onto GiFi Technology.
2. What is Gi-Fi?
Gi-Fi or gigabit wireless is the world’s first transceiver integrated on a single chip that operates
at 60GHz on the CMOS process. It will allow wireless transfer of audio and video data at up to 5
gigabits per second, ten times the current maximum wireless transfer rate, at one-tenth the cost.
NICTA researchers have chosen to develop this technology in the 57-64GHz unlicensed
frequency band as the millimeter-wave range of the spectrum makes possible high component
on-chip integration as well as allowing for the integration of very small high gain arrays. The
available 7GHz of spectrum results in very high data rates, up to 5 gigabits per second to users
within an indoor environment, usually within a range of 10 meters. It satisfies the standards of
IEEE 802.15.3C
2.1 Architecture of Gi-Fi:
The core components of a Gi-Fi system is the subscriber station which available to several access
points. It supports standard of IEEE 802.15.3C supports millimeter-wave wireless pan network
used for communication among computer devices (including telephones and personal digital
assistants) close to one person. An 802.15.3C based system often uses small antenna at the
subscriber station. The antenna is mounted on the roof. It supports line of sight operation.
2.2 Fundamental Technologies in 802.15.3C:
This millimeter-Wave WPAN will operate in the new and clear band including 57-64 GHz
unlicensed band defined by FCC 47 CFR 15.255. The millimeter-wave WPAN will allow high
coexistence (close physical spacing) with all other microwave systems in the 802.15 family of
WPANs.
2.3 Working in Gi-Fi:
Here we will be use a time division duplex for both transmission and receiving. The data files are
up converted from IF range to RF 60Ghz range by using 2 mixers. We will feed this to a power
amplifier, which feeds millimeter-wave antenna.
The incoming RF signal is first down converted to an IF signal centered at 5 GHz .and then to
normal data ranges, here we will use heterodyne construction for this process to avoid leakages
due to direct conversion. Due to availability of 7 GHz spectrum the total data will be transferred
within seconds.
2.3.1 Time-division duplex
Time-Division Duplex (TDD) is the application of time-division multiplexing to separate
outward and return signals. It emulates full duplex communication over a half duplex
communication link. Time division duplex has a strong advantage in the case where the
asymmetry of the uplink and downlink data speed is variable. As uplink traffic increases, more
channel capacity can dynamically be allocated to that, and as it shrinks it can be taken away. For
radio systems that aren't moving quickly, another advantage is that the uplink and downlink
radio.
2.4 Why 60 GHz..?
Here we will use millimeter wave antenna which will operate at 60 GHz frequency which is
unlined band .Because of this band we are achieving high data rates energy propagation In the 60
GHz band has unique characteristics that make possible many other benefits such as excellent
immunity to co-channel interference, high security, and frequency re-use.
Point-to-point wireless systems operating at 60 GHz have been used for many years for satelliteto-satellite
communications. This is because of high oxygen absorption at 60 GHz (10-15
dB/Km). This absorption attenuates 60 GHz signals over distance, so that signals cannot travel
far beyond their intended recipient. For this reason, 60GHz is an excellent choice for covert
communications
2.5 ULTRA WIDE BAND FREQUENCY USAGE:
UWB, is a technology with high bit rate, high security and faster data transmission. It is a zero
carrier technique with low coverage area. So we have low power consumption. These features
are Ultra-Wideband (UWB) is a technology for transmitting information spread over a large
bandwidth (>500 MHz) that should, be able to share spectrum with other users. Regulatory
settings of FCC are intended to provide an efficient use of scarce radio bandwidth while enabling
both high data rate personal-area network (PAN) wireless connectivity and longer-range, low
data rate applications as well as radar and imaging systems.
3. FEATURES OF Gi-Fi
The Gi-Fi standard has been developed with many objectives in mind. These are summarized
below:
3.1 Advantages
3.1.1 High speed of data transfer:
The main invention of Gi-Fi is to provide higher bit rate .As the name itself indicates data
transfer rate is in Giga bits per second. Speed of Gi-Fi is 5 Gbps, which is 10 times the present
data transfer. Because of this high speed data transfer, we can swap large video, audio, data files
within seconds. Because of wider availability of continuous 7 GHz spectrum results in high data
rates.
3.1.2 Low Power Consumption:
As the large amount of information transfer it utilizes milli-watts of power only. It consumes
only 2mwatt power for data transfer of gigabits of information, where as in present technologies
it takes 10mwatt power, which is very high.
3.1.3 High Security:
As the IEEE 802.15.3C provides more security, it provides link level and service level security,
where these features are optional.
Point-to-point wireless systems operating at 60 GHz have been used for many years by the
intelligence community for high security communications and by the military for satellite-to
satellite communications. The combined effects of O2 absorption and narrow beam spread result
in high security and low interference