Brief information about 4G

1. 4G Mobile Communication
Dr. Varun Kumar
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2. Outlines
1 Introduction
2 End user expectation
3 Wireless Resource
4 Generation wise comparison
5 Technological improvement and limitation of 4G:
6 References
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3. Introduction:
Introduction to Communication
Communication is a process through which transmitter send information to
the receiver.
Challenges of Effective Communication:
1 Power
2 Bandwidth
3 Latency (delay)
4 Noise
5 To build robust signal processing for interference cancellation and
many more
Note: Based on the user demand and expectation the governing body
like international telecommunication union (ITU) decides, which
technology is called as 1G, 2G,...5G or beyond.
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4. End User Expectation
Source of Information/ Type of Data
1 Text
2 Audio
3 Video
Data Rate
Rb = B log2 1 +
P
I + N
B → Available bandwidth
P → Signal power
I → Interference (ISI, ICI, ACI, inter-user interference and so on)
N → Noise power (AWGN and colored noise)
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5. Wireless Resource:
Wireless Resource
1 Power
2 Time
3 Frequency
4 Space (No. of antenna across Tx /Rx unit)
5 Code
Technological Challenge:
Improvisation of spectrum-efficiency (SE)
Improvisation of energy-efficiency (EE)
Reduction of processing latency
Sharp beam formation for mitigating the inter-user interference at
same time-frequency slot.
Better precoding and decoding scheme adoption for improving data
rate and many more.
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6. Generation wise comparison
Brief Comparison from 2G to 4G
Parameter 2G/2.5G/2.75G 3G 4G
Operational Time 1990-2002 2002-2012 2012-2020
Carrier Frequency 900 MHz
1755-
1855 MHz
2.3GHz
/ 2.6GHz
Bandwidth 200 KHz 5 MHz 10/20 MHz
Peak Data Rate 144 Kbps
384 Kbps
-2Mbps
100 Mbps-
1 Gbps
Digital Modulation
Technique
GMSK
8-PSK
QPSK/
16-QAM
QPSK/16-QAM
128/256 QAM
Multiple Access
Technique
FDMA
TDMA
CDMA
OFDM
OFDMA
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7. Technological Improvement in 4G
1 Instead of TDMA or FDMA, 4G standard uses OFDMA.
2 Wide-band signal processing could be feasible.
3 In 3G only 2 × 2 MIMO was possible, whereas 8 × 8 MIMO in 4G.
4 Enhanced multiplexing and diversity capability in 4G .
5 Large number of user support.
6 Removal of near-far problem .
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8. Limitation of 4G:
Limitation of 4G
There is no scope of beyond sub-6GHz communication.
Due to higher data demand, like online gaming, IoT, augmented
virtual reality, space exploration and many more.
Limited number of antenna support is in 4G.
Latency is also high as per user demand.
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9. Thank You
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10. References
F. Khan, LTE for 4G mobile broadband: air interface technologies and
performance. Cambridge university press, 2009.
E. Dahlman, S. Parkvall, and J. Skold, 4G: LTE/LTE-advanced for mobile
broadband. Academic press, 2013.
S. Y. Hui and K. H. Yeung, “Challenges in the migration to 4g mobile systems,”
IEEE Communications magazine, vol. 41, no. 12, pp. 54–59, 2003.
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