06-03-2013, 03:12 PM
Printed Dipole Antennas for Personal Communication Systems
[attachment=52783]
Abstract
Emergent wireless systems based on personal communication standards are demanding new antennas
with better performance in order to increase the distance of communications, to provide wider bandwidth
and, in some case, to allow multiband behavior. The use of printed dipole antennas is highly recommended
in these applications. In this paper, we report on different printed dipole antennas for wireless communica-
tions in particular scenarios. For point-to-point communications we propose two printed Yagi-like antennas
with a high gain and low cost. For broadband communications we discuss the use of log-periodic printed
dipoles antennas. Finally, for multiband communication systems, dual-band printed dipole antennas are
investigated. In any case, some illustrative designs, for specific applications, are described. They are also
analyzed by means of FDTD simulations and compared with standard measurements such as insertion
losses and radiation patterns.
Introduction
Nowadays, different telecommunication protocols,
systems, and networks have born in order to satisfy the
requirements of recent wireless technologies. Some of the
well-established wireless standards are Bluetooth, Wi-Fi,
and UWB (ultra wide band). Bluetooth (IEEE 802.15.1
standard) is used for low-transmission-rate applica-
tions at 2.45 GHz, for near-user devices like cell phones,
handheld terminals, printers, etc. Wi-Fi (IEEE 802.11x
standard) simultaneously works within the 2.45-GHz
and 5.5-GHz bands and is used in WLANs (wireless local
area networks), with transmission rates ranging from
54 Mbps to 600 Mbps (802.11n protocol). UWB is used
for linking close devices (typically 10 m) with low cost
and low energy consumption. This last protocol allows a
very high transmission rate (from current 100–200 Mbps
to expected 480 Mbps in the near future) and uses a wide
frequency band (3.1–10.6 GHz). Typical UWB applica-
tions are wireless USB connectivity (W-USB), wireless
connectivity between multimedia systems (photograph
and video camera), and personal computers.
Point-to-point Communications
In point-to-point communication systems, both the
transmitter and the receiver are static. In this case, the
use of directional antennas is highly recommended, both
for reducing interferences coming from other wireless
systems and for increasing the communication distance.
Three strategies are usually considered to increase the
antenna gain: to design specific antenna geometries, to
add parasitic elements to the basic antenna structure,
and to use antenna arrays.
Broadband Personal Communication
Systems
The increasing number of users and applications of
personal wireless systems has promoted the use of new
broadband and multiband standards. These standards,
like Wi-Fi, WiMAX, and UWB, allow a higher number
of simultaneous users and a higher communication rate.
The antennas used with these new standards need to be
broadband or multiband.
Conclusions
Printed dipoles antennas have demonstrated to be good
candidates for new wireless communication systems.
In point-to-point applications, directive antennas are
needed, so printed Yagi-like antennas can be used. A
low-cost printed circuit board can be used in applica-
tions within the ISM 2.45-GHz band. Uniplanar Yagi-
like antennas, fabricated onto one side of the dielectric
substrate, provide simple fabrication, a moderate-to-high
gain with a low size (measured gain of 5.5 dBi with a
size of 1.38 l2 for the six-director prototype) and good
electric characteristics (with a bandwidth better than
16%). Biplanar Yagi-like antennas, fabricated on both
sides of the substrate, offer a higher gain with a lower
size (measured gain of 7.9 dBi with a size of 0.75 l2 for
the five-director antenna) with slightly worse fabrication
and return loss results.
[attachment=52783]
Abstract
Emergent wireless systems based on personal communication standards are demanding new antennas
with better performance in order to increase the distance of communications, to provide wider bandwidth
and, in some case, to allow multiband behavior. The use of printed dipole antennas is highly recommended
in these applications. In this paper, we report on different printed dipole antennas for wireless communica-
tions in particular scenarios. For point-to-point communications we propose two printed Yagi-like antennas
with a high gain and low cost. For broadband communications we discuss the use of log-periodic printed
dipoles antennas. Finally, for multiband communication systems, dual-band printed dipole antennas are
investigated. In any case, some illustrative designs, for specific applications, are described. They are also
analyzed by means of FDTD simulations and compared with standard measurements such as insertion
losses and radiation patterns.
Introduction
Nowadays, different telecommunication protocols,
systems, and networks have born in order to satisfy the
requirements of recent wireless technologies. Some of the
well-established wireless standards are Bluetooth, Wi-Fi,
and UWB (ultra wide band). Bluetooth (IEEE 802.15.1
standard) is used for low-transmission-rate applica-
tions at 2.45 GHz, for near-user devices like cell phones,
handheld terminals, printers, etc. Wi-Fi (IEEE 802.11x
standard) simultaneously works within the 2.45-GHz
and 5.5-GHz bands and is used in WLANs (wireless local
area networks), with transmission rates ranging from
54 Mbps to 600 Mbps (802.11n protocol). UWB is used
for linking close devices (typically 10 m) with low cost
and low energy consumption. This last protocol allows a
very high transmission rate (from current 100–200 Mbps
to expected 480 Mbps in the near future) and uses a wide
frequency band (3.1–10.6 GHz). Typical UWB applica-
tions are wireless USB connectivity (W-USB), wireless
connectivity between multimedia systems (photograph
and video camera), and personal computers.
Point-to-point Communications
In point-to-point communication systems, both the
transmitter and the receiver are static. In this case, the
use of directional antennas is highly recommended, both
for reducing interferences coming from other wireless
systems and for increasing the communication distance.
Three strategies are usually considered to increase the
antenna gain: to design specific antenna geometries, to
add parasitic elements to the basic antenna structure,
and to use antenna arrays.
Broadband Personal Communication
Systems
The increasing number of users and applications of
personal wireless systems has promoted the use of new
broadband and multiband standards. These standards,
like Wi-Fi, WiMAX, and UWB, allow a higher number
of simultaneous users and a higher communication rate.
The antennas used with these new standards need to be
broadband or multiband.
Conclusions
Printed dipoles antennas have demonstrated to be good
candidates for new wireless communication systems.
In point-to-point applications, directive antennas are
needed, so printed Yagi-like antennas can be used. A
low-cost printed circuit board can be used in applica-
tions within the ISM 2.45-GHz band. Uniplanar Yagi-
like antennas, fabricated onto one side of the dielectric
substrate, provide simple fabrication, a moderate-to-high
gain with a low size (measured gain of 5.5 dBi with a
size of 1.38 l2 for the six-director prototype) and good
electric characteristics (with a bandwidth better than
16%). Biplanar Yagi-like antennas, fabricated on both
sides of the substrate, offer a higher gain with a lower
size (measured gain of 7.9 dBi with a size of 0.75 l2 for
the five-director antenna) with slightly worse fabrication
and return loss results.