MIMO uses multiple antennas at both the transmitter and receiver to improve wireless communication performance. It takes advantage of multipath propagation by using spatial diversity or spatial multiplexing. With spatial diversity, the same information is transmitted from different antennas to improve reliability and coverage. With spatial multiplexing, different data streams are transmitted from different antennas to increase data rates. MIMO can significantly increase capacity, quality, and spectral efficiency compared to single-input systems. It is used in technologies like 3G, 4G, and will be important for 5G networks.

1. MIMO In Wireless Communication
Kailash Karki
M.Tech(Communication and Radar System)
ID No:152040006
kailash202012@gmail.com

2. Introduction
• MIMO stands for Multiple Input Multiple
Output.
• Technology that used multiple antenna in
transmitter side as well as in receiver side.
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3. Problem Statement
• Capacity
C=B*log2(1+SNR)
• Quality
• Coverage
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4. Multipath Propagation
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5. Existing Systems Before MIMO
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6. MISO
-Multiple Input Single Output
-Also called Transmitter Diversity
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7. SIMO
• Single input Multiple Output
• Also called Receiver diversity
• Out of two signals the receiver processes
strongest one.
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8. How MIMO works?
• MIMO takes advantages of Multipath.
• MIMO uses multiple antennas to send multiple parallel signals
(from transmitter).
• In an urban environment, these signals will bounce off trees,
buildings, etc. and continue on their way to their destination (the
receiver) .
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9. Continue:
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• “Multi-path” occurs when the different signals
arrive at the receiver at various times.
• With MIMO, the receiving end uses an algorithm
or special signal processing to sort out the
multiple signals to produce one signal that has
the originally transmitted data.
• Multiple data streams transmitted in a single
channel at the same time.
• Multiple radio collects multipath signals.
• Adaptive signal processing at both transmitter
and receiver

10. Formats For MIMO
• Spatial Diversity:
- Same information is transmitted by different antenna.
- Improves the link reliability.
- Improves the coverage.
• Spatial Multiplexing:
-Information is divided into number of streams.
-Different antenna transmit different data streams.
-Increase the data rate.
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11. MIMO Diversity and MIMO Multiplexing
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12. MIMO System Model
Transmit Vector MIMO Channel Received vector
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X1
X2
X3
.
.
XM
Y1
Y2
.
.
YN
M*1 Matrix N*1 Matrix
N*M Matrix

13. Contn.........
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• Y=h x + n

14. Multipath is enemy????
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15. MIMO Capacity
• Capacity of MIMO system:
C=n*B*log2(1+SNR)
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16. Advantages of MIMO
• Takes advantage of Multipath propagation.
• Increased Capacity.
• Increased Quality.
• Spectral Efficiency.
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17. Applications
• HSPA+(3G)
• WiMax (IEEE 802.16)
• LTE(4G)
• 5G (proposed)
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18. Thank you
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