1. FSS Enhancement of Multipath for
MIMO/4G Wireless Communications
Supervisor
Dr Peter Callaghan
Presentation By
Devinder Pal Singh
MSc Electronics and Communications

2. Introduction
This Project deals with the coverage
issues being faced in Modern Offices
such Large data files transfers.
Transcieve of signals for large data
files via Wireless mode
The Frequency Selective Surfaces
and multiple Inputs and Multiple
Outputs could be used together for
resolving coverage issues in Modern
offices to transfer large data files.
Low cost signal could be transferred
at same frequency.
Advantages
1. Mobilize and High Performance
2. Data Transfer at High Speeds.
3. Low Cost.
4. Less Layout of Cable .
5. Security
6. Less chances of fading of
signals especially in the room
corners and dead areas such as
base.
7. Low interference.
Note: The output of FSS with MIMO depend upon the size of the
reflective FSS material.

3. Block Diagram for FSS Enhancement of
Multipath for MIMO/4G Wireless
Communications
WLAN Device
MIMO
Transmitter
WLAN Device
MIMO
Receiver
FSS
FSS

4. Objectives
• Discover the device capabilities which could
reflect multiple inputs and multiple outputs.
• Evaluation, design and testing of suitable
Frequency Selective Surface structures.
• Evaluation of file transfer protocols to transfer the
data between two communication devices.
• Design a platform with FSS and MIMO
equipment which could transfer larger data files at
the speed of 2-5Mbps in indoor environment.

5. Project Deliverables
• Review MIMO Systems-Identify candidate
hardware for test (WLAN).
• FSS (band stop at 2.4GHz) design.
– Design Method
– Experimental Hardware
– Frequency Response (Transmission) Results.
• Enhanced Multipath Experiment –Results.

6. Implementation

7. FSS Design Fabrication
•Solid Works Software
•ARES Software

8. Design Model For FSS Testing in Anechoic
Chamber
101cm
146cm
58cm
10cm
Radius 8.5cm
60 cm
101cm
3cm
3cm
Wooden
support
Lengths
Wooden Base to
support
Sheet/FSS
Wooden base to
connect support with
Antenna Pole
Wooden Base
Design Model to Support the FSS in front of Antenna Pole

9. Wooden Design Model for FSS
Testing
1.7-2.4GHz
Horn Antenna
Wooden Support
Lengths (Rods) for the
placement of FSS
Absorbent material
Anechoic Chamber Inside and placed with the wooden design model for measurements
Antenna Pole
Scale distance used to
measure frequency Response
at different scale

10. 25 Square Loop FSS Design was made
with Solid State Works
S=2mm
g=3mm
Square loop array/matrix designed with Solid State Works

11. FSS Designed with the ARES Software
Square Loop Array Designed with the ARES Software
Gap of 3mm between
square length
Square Loop with the
thickness of 2mm

12. ARES Software
297mmx210mm FSS design developed with
ARES Software shown in the figure below.
PCB Square Loop Array designed with Ares Software

13. FSS Design Under Testing
1.7GHz-2.4GHz Horn Antenna
Wooded block being used as scale to
check frequency response at different
scale.
Square Loop Array /FSS under
observation
FSS Design Under Test

14. Block diagram of Implementation of FSS with
4G/Wireless
Reflector (FSS)
Comm.
Device with
MIMO
Device
Wireless MIMO Antenna
Coaxial cable
Absorbing
Material
Network Analyser
Reflector (FSS)

15. Setup of MIMO/FSS for File Transfer
Aerial Antenna
FSS/MIMO devices installed inside /outside chamber for large data transfer
FSS
MIMO Devices

16. Results
Frequency Responses of
FSS

17. Frequency Response of
Solid State Works FSS
The response was taken at a
distance of 500 mm.
• The top curve represents a
normalized response.
• The bottom curve
represents a band stop at
2.2GHz at -33.2 dB .
• Ripples were also found as
due to dimension of the
copper strip of not correct
thickness and also of no
proper gap of 3mm.
Frequency Response of Solid State Works FSS

18. Frequency Responses of Etched Sheet
S
No.
Frequency
Response
Distance
(Millimetre
s)
Frequency
Response
Measured (dB)
1st
Band
Stop
Frequency
Response
Measured
(dB)
2nd
Band
Stop
1 650 -51.257 2.153 -36 2.08
2 620 -24.33 2.08 -32 2.4
3 700 -40.42 1.9 --- ---
4 800 -23.76 2.26 ---- ----
The Curve dipped to -51.257
dB at 2.15GHz and -36dB at
2.08 GHz .
Frequency Response at 650mm
Table Shows list of frequency responses
taken at different scales.

19. Test Done With MIMO Modems with
FSS Designed
After the MIMO Modems Have been Setup the tests were done.
Four Tests have been planned
 Measuring data speed between two devices of large data inside the
anechoic chamber,
 Using One Horizontal Antenna of Antenna installed in Anechoic
Chamber with One Modem Setup Installed inside the chamber.
 Using One Vertical Antenna of Antenna installed in Anechoic
Chamber with One Modem Setup Installed inside the chamber.
 Using Horizontal and Vertical Antenna of Antenna installed in
Anechoic Chamber with One Modem Setup Installed inside the
chamber.

20. Data Transfer Speed
Measurements
MIMO/FSS Design

21. Data Transfer Speed in Anechoic Chamber Kbps
With/Without MIMO and FSS.
0
1000
2000
3000
4000
5000
6000
1 2 3 4 5 6
Transfer Speed without MIMO
Transfer with DongleWithOut Reflector
Transfer with With Reflector
Graph Shows speed measurement with/ without MIMO &
Reflector

22. Data Speed in Corners/DUT
Table Shows test Results done with MIMO and FSS at the
corners/Device Under Test area of Anechoic Chamber.
S No. Corner Right Side Area with both antennas Only one Horizontal Antenna Only one Vertical Antenna
13846 3456 2897
24004 3567 3133
34018 3689 3421
44078 3891 3678
S No. Corner Left Side Area with both antennas Only one Horizontal Antenna Only one Vertical Antenna
13340 3456 2897
23432 3567 3133
33679 3689 3421
43879 3891 3678
S No. Below DUT(Device Under Test) Area One Horizontal Antenna One Vertical Antenna
1 2233 2021 2111
2 2571 2111 2213
3 2633 2232 2345
4 2909 2324 2355

23. Data transfer speed analysis in
different areas (Kbps)
0
500
1000
1500
2000
2500
3000
3500
4000
4500
1 2 3 4
Corner Right Side Area with both antennas
Corner Left Side Area with both antennas
Below DUT(Device Under Test) Area

24. Conclusion
• The FSS enhancement of Multipath for Multi Input
Multi Output was successfully designed and tested.
Results were analysed at different distances from the
device under test area. From the results the response
of -51.257dB at 2.153 at 650mm distance from the
device under test area and a satisfactory behaviour of-
32dB at 2.4GHz was .
• Large data filestransferred at a speed 4-5.2Mbps in the
normal indoor office location, 2-3Mbps in the
basement areas and 3-4.5Mbps in the room corners .

25. Future Work
In order to have transfer large data files at speed
a high speed.
- A Larger FSS would be beneficial.
- Full version File transfer protocols would be
beneficial for speed analysis.
- Analysis of data speed of 2.4 GHz for better
indoor communications.

26. Thanks You