WPAN technology aims to provide a reliable wireless communication between computer, portable devices & consumer electronics within short range.This requires high data rate. Therefore, UWB technology has been designed & developed to meet this demand. For this, UWB antennas are essential.

1. A SMALL COUPLE
SLOTTED ANTENNA FOR
UWB APPLICATION
(Yusnita Rahayu,Tharek A.Rahman, Razali Ngah)
978-1-4244-4076,2009,IEEE
Presented by:
JIGYASA SINGH
M.TECH(ECE)

2. Introduction
• WPAN technology aims to provide a reliable wireless
communication between computer, portable devices &
consumer electronics within short range.
• This requires high data rate.
• Therefore, UWB technology has been designed & developed to
meet this demand.
• For this, UWB antennas are essential.

3. Features
• Uses a couple of L and U slot.
• Truncated ground plane is used to control antenna impedence
matching.
• Fed by microstrip line, alignment error results in degradation of
antenna performance.
• Dimension- 30mm x 30mm.

4. Geometry of L and U couple slotted antenna
The pentagonal antenna is
vertically installed above a
ground plane (lgrd) of 11 mm. The
optimum feed gap (h) to the
ground plane is found to be 1.5
mm. The dimension of substrate
is chosen to be 30 x 30 mm2 (Wsub
x Lsub). Antenna has a pentagonal
patch with a width (w) of 15 mm
and a length (l) of 12 mm.

5. Why & How?
• UWB range- 3.1 Ghz to 10.6 Ghz, this antenna is giving a
omnidirectional pattern over this range.
• Good return loss with respect to -10 db.
• These slots are designed investigating the behaviour of current
flow distribution of patch antenna.

6. Factors choosing antenna topology
• Physical profile.
• Compatibility.
• Impedence.
• Radiation efficiency.
• Radiation pattern.

7. L slot & U slot
• Length of L slot = 14.5 mm approx. equal to 0.25λ at 5.3 Ghz.
• Length of U slot = 11.5 mm approx. equal to 0.4λ at 10.3 Ghz.
• L slot = improves lower dip resonance.
• U slot = improves upper dip resonance.
• L SLOT + U SLOT = GOOD RETURN LOSS at -10 db.

8. Measured & simulated return loss for L &
U couple slotted antenna.

9. E plane & H plane
• Simulated & measured E & H plane for 4 Ghz & 5.8 Ghz.
• H plane shows good-omnidirectional pattern for both frequency
range.
• E plane shows broad & slight distorted & slightly distorted at 5.8
Ghz.

10. Measured & simulated radiation pattern
for L & U slotted antenna.

11. Working
• Current distribution is simulated by using Zeland FDTD
simulation software.
• Current along the edges introduces a additional resonance +
resonance of the main patch = broadband frequency
characterstic.

12. Conclusion
• A small couple slotted of L and U antenna has been presented.
• This antenna uses two coupling slots with a partial ground plane for bandwidth
enhancement.
• An experimental prototype has been designed, fabricated and tested.
• The measured return losses cover the UWB bandwidth requirements of 2.5 GHz –
10.1 GHz with respect to -10 dB.
• The measured radiation patterns of this prototype are also presented at
frequencies 4, and 5.8 GHz, respectively.

13. FutureWork
• From the graph we saw that E plane shows slightly distorted radiation pattern.
• The improvement can be achieved by cutting out the edges of the finite ground
plane.
• This produces a phase shift between the induced equivalent magnetic currents on
the edges, thereby causing cancellation in the diffracted fields.
• We can numerically and experimentally examined the effects for some patch
antennas and confirmed that the distortions in E plane pattern could be
eliminated by using this approach.