VIJAY_Internship_ppt

Investigation and Simulation of Antennas for 4G LTE-A MIMO Systems

Presented By:

Vijaykumar Kulkarni

Academic Supervisor: Industrial Supervisor:

Prof. Dr. Ing Heinz Schmiedel Dipl-Ing Mr. Heinrich Fehn

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PIFA Antenna Simulation

• Importing CAD file

• Setting frequency range & field monitors

• Global & local mesh settings

• Use of AR filter to reduce truncation errors for S-parameters

• Comparison of results for AR filter versus lower energy limit

• Hexahedral & tetrahedral mesh viewing

• F-Solver & T-Solver results comparison

• Adaptive mesh refinement for verification of results

• Antenna matching in CST Design Studio

• Defining new task- S-parameter simulation

• Return loss results comparison for matched and unmatched cases

• AC task settings

• Far field & E field results comparison for matched and unmatched cases

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Results

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Flashing, assembling & testing of Audi displaydevices- task assigned by Thomas Göggelmann

• Flashing of the new updated version of firmware on the pcb of display device.

• Assembling of flashed display with the IC and its mechanical enclosure.

• Testing of the display(testbild); flashing & reflashing of the display; CAN interfacing and verification of SPI read/write capability of the device; touchscreen & external touch interface testing & verification.

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MIMO concept for Antennas

• MIMO builds on Single-Input Multiple-Output (SIMO), also called receive diversity, as well as Multiple-Input Single-Output (MISO), also called transmit diversity.

• So how does MIMO work?1. MIMO capacity gains come from taking advantage of spatial diversity in the

radio channel2. Depending on channel conditions and noise levels, the rank (number of

simultaneous streams) can be varied for example the number of streams can be reduced under poor conditions

3. The performance can be optimized using precoding

• For MIMO to work:Must have at least as many receivers as transmitted streamsMust have spatial separation at both transmit and receive antennasMore transmitters enables beamforming in addition to MIMOBest multipath conditions for MIMO optimization

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Antenna Diversity: In this technique, we make use of multipleantennas to receive a signal so that we can combine the replicas ofthe received signal in a constructive manner so as to improve thesystem performance. As a result we can have better SNR & Gain.Statistical analysis is used for assesing the performance of spatialdiversity whereas 3D cross correlation function is utilized for theperformance verification of the other two techniques. Differentmethodologies employed:

1. Polarization Diversity: Employing of orthogonally polarized antennas.2. Spatial Diversity: Placing antennas away from each other so that

they can sample signals that are fairly decorrelated.3. Pattern Diversity: Use of mutiple antennas having different gains in

different directions, which results in variable weighting factors forthe received multipath components.

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Advantages of MIMO:• Spatial multiplexing• Reduction in BER & Enhancement of data rate• Increment in SNR and SINR• Minimization of fading effects• Improvement of channel capacity & spectral efficiency• Expansion of cell coverage & rise in average cell throughput• Reliability & lower susceptibility for tapping by unauthorized users

Disadvantages:• If correlation between antennas is high then channel capacity & diversity gain falls

& multiple stream tx-rx will not be supported• Two antennas at opposite ends of the same handset (counterpoise) will tend to

excite the same radiating mode and effectively have the same radiation pattern implying high correlation & low isolation.

• Stringent implications on location and orientation of antennas & it becomes more crucial in the case of handheld devices.

General Antenna design requirements & factors affecting the real time performance

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• Isolation (20 dB min. Improved by shaping antennas‘ near field)• Return loss (10 dB min. Can be achieved by Matched termination &

reduced correlation between adjacent antennas)• Radiation efficiency• Multiband support• Location (min. apart) & orientation of antennas so as to achieve

the required bandwidth• Controllable directivity for utilizing beam forming

techniques(Improvement of SNR in non MPP environment)• SINR of 15dB minimum for MIMO• Antenna ground impedance (should be minimum)• Selectivity & frequency stability• Flexible implementation without sacrificing gain• Cross-polar discrimination • SAR & HAC compliance(Maximum TX power can be -41.3dBm/MHz)

Antenna requirements for the reference antenna• 4x4 MIMO Antenna system

• 4 antennas for simulation & implementation

• Individual Antenna performance requirements:

• Return loss: Min. 10dB(or 6dB)

• Antenna efficiency: >-3dB in free space

• Multiband support: LTE 700(690-798), GSM 850(824-894), GSM 900(880-960), GSM 1800(1710-1880), GSM 1900(1850-1990), UMTS/WCDMA 2100(1920-2170; 2110-2200), LTE 2300(2305-2400), LTE 2500(2500-2690), LTE 3500(), GNSS(1560-1620), WiFi 5GHz(5150-5850)

• All the 4 antennas must have almost omnidirectional pattern

• Antenna ground impedance (should be min.)

• MIMO Antenna system requirements:• Isolation: (20 dB min.)

• Envelope correlation coefficient (ECC) between received signals of different antennas.(It should be less than 0.5 so as to have the advantage of Spatial Diversity.)

• Controllable directivity for utilizing beam forming techniques(Improvement of SNR in non MPP environment)

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Antenna requirements for the reference antenna continued..

• Diversty:

• Spatial Diversity: Location (min. λ/2 apart & orientation of antennas)

• Polarization Diversity: Cross-polar discrimination

• Pattern Diversity: Use of mutiple antennas having different gains in different directions

• Diversity Gain

• Branch power ratio (k): a measure of power balance between antennas in MIMO system. It should be between 0 and 3 dB.

• Branch Power imbalance: Mean Effective Gain (Gain balance ratio) (MEG) (<3dB)

• Cross polarization ratio (XPR)

• MIMO Capacity

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Hindrances• Lower antenna coupling doesn‘t ensure lower correlation & vice versa.

• Antenna coupling (Currents induced in the common ground plane)

• Direct radiation between different antennas

• Scattering from nearby objects

• Envelope cross-correlation

• It is very difficult to achieve high gain and low correlation across multiple bands.

• Similarly, implementation of antennas with high efficiency that are gain balanced and independent of each other are also not easy to achieve.

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Monopole Dipole Layered

AntenovaTaoglas

Taoglas Antenna: Anechoic chamber passive measurement setup for 2.4Ghz & 5GHz bands

Copyright e.solutions1/19/2016

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Taoglas Antenna: 2.4GHz band 3D view@2440MHz ρ=4m; view at Φ=0°, θ=90° & Ψ=180°


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Taoglas Antenna: 2.4GHz band 1D plot@2440MHz cut taken at Φ=90° over all θ´s


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Taoglas Antenna: 2.4GHz band RL, Radiation & Total Efficiency in dB over all specified frequencies


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Taoglas Antenna: 2.4GHz band Maximum Gainin dBi over all specified frequencies


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• Input Power to test Antenna: 16dBm

• Input Signal Frequency: 5.5GHz

• Separation Distance: 50cm

Isolation Characteristics measurement for MonoconeAntenna(test) with reference to Horn

Antenna(reference)

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Summary of comparison CTS open / closed and Shielding box open / closed

Sheilding box delta open to closed: 24 dB Sheilding box delta open to closed: 30 dB

CTS delta open to closed: 6 dB CTS delta open to closed: 12dB

Facing in front

Facing in front

Facing sideways

Facing sideways

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Ref -9 dBm Att 20 dB

RBW 500 kHz

VBW 20 Hz

SWT 2.5 s

*

*

1 PK

VIEW

2 PK

VIEW

* A

3DB

-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

1

Marker 1 [T1 ]

-20.54 dBm

5.499983974 GHz

2

Delta 2 [T2 ]

-29.06 dB

0.000000000 Hz 1

Delta 1 [T1 ]

0.00 dB

0.000000000 Hz

Date: 15.JUN.2015 13:46:23

Sheilding box delta open to closed: 24dB

Ref -9 dBm Att 20 dB

*

*

1 PK

VIEW

2 PK

MAXH

* A

3DB

RBW 500 kHz

VBW 20 Hz

SWT 2.5 s

-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

1

Marker 1 [T1 ]

-20.54 dBm

5.499983974 GHz

2

Delta 2 [T2 ]

-46.83 dB

0.000000000 Hz 1

Delta 1 [T1 ]

0.00 dB

0.000000000 Hz

Date: 15.JUN.2015 14:24:25

Sheilding box delta open to closed: 24dB

VIJAY_Internship_ppt

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