EC635 Advanced Topics in Communication Systems R. S. Kshetrimayum A.3 Cellular Concepts Topics: A.3.1 Frequency reuse A.3.2 Cluster and Capacity A.3.3 Reuse distance A.3.4 CCI and system capacity A.3.5 SIR Introduction: The design objective of early mobile radio systems was to achieve a large coverage area using a single, high powered transmitter with an antenna mounted on a tall tower The cellular concept is a system-level idea which calls for replacing a single, high power transmitter (large cell) with many low power transmitter (small cells) each providing a coverage to only a small portion of the service area While it might seem natural to choose a circle to represent the coverage of a BS, adjacent circles cannot be overlaid upon a map without leaving gaps or creating overlapping regions Thus when considering geometric shapes which cover an entire region without overlap and with equal area, there are three sensible choices – a square, an equilateral triangle and a hexagon The actual radio coverage of a cell is known as footprint and is determined from field measurements or propagation prediction models (a) (b) (c) Fig. A.3. 1 (a) Theoretical Coverage (b) Ideal Coverage (c) Real Coverage
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A.3 Cellular Concepts - iitg.ac.in · A.3 Cellular Concepts Topics: A.3.1 Frequency reuse A.3.2 Cluster and Capacity ... cellular BSs is called frequency reuse or frequency planning
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EC635 Advanced Topics in Communication Systems R. S. Kshetrimayum
A.3 Cellular Concepts
Topics:
A.3.1 Frequency reuse
A.3.2 Cluster and Capacity
A.3.3 Reuse distance
A.3.4 CCI and system capacity
A.3.5 SIR
Introduction:
� The design objective of early mobile radio systems was to achieve a large
coverage area using a single, high powered transmitter with an antenna
mounted on a tall tower
� The cellular concept is a system-level idea which calls for replacing a single,
high power transmitter (large cell) with many low power transmitter (small
cells) each providing a coverage to only a small portion of the service area
� While it might seem natural to choose a circle to represent the coverage of a
BS, adjacent circles cannot be overlaid upon a map without leaving gaps or
creating overlapping regions
� Thus when considering geometric shapes which cover an entire region without
overlap and with equal area, there are three sensible choices – a square, an
equilateral triangle and a hexagon
� The actual radio coverage of a cell is known as footprint and is determined
from field measurements or propagation prediction models