SMART ANTENNAS : SMART ANTENNAS PRESENTATION BY
ECE CONTENTS : CONTENTS WHAT IS SMART ANTENNA ?
TYPES OF SMART ANTENNAS
SWITCHED BEAM ANTENNAS
ADAPTIVE ARRAY ANTENNAS
COMPARISION BETWEEN SWITCHED BEAM AND ADAPTIVE ARRAY
SDMA(SPACE DIVISION MULTIPLI ACCESS)
SMART ANTENNA VS OTHER ANTENNA
OVERVIEW OF SMART ANTENNA SYSTEM (SAS) FOR MOBILE COMMUNICATION
SMART ANTENNA USED TO OPTIMISE CDMA CAPCITY
CONCLUSION What is SMART ANTENNA ? : What is SMART ANTENNA ? A smart antenna consists of an antenna array, that changes the array pattern in response to Signal environment to improve the performance of a communication system TYPES OF SMART ANTENNA : TYPES OF SMART ANTENNA Smart antenna systems are customarily categorized into ,
SWITCHED BEAM ANTENNA
ADAPTIVE ARRAY ANTENNA SWITCHED BEAM ANTENNAS : SWITCHED BEAM ANTENNAS These antenna systems detect signal strength, choose from one of several predetermined, fixed beams, and switch from one beam to another as the mobile moves throughout the sector. SWITCHED BEAM ANTENNAS : SWITCHED BEAM ANTENNAS Figure- Switched Beam System Coverage Patterns (Sectors) ADAPTIVE ARRAY ANTENNAS : ADAPTIVE ARRAY ANTENNAS Adaptive antenna technology provides optimal gain while simultaneously identifying, tracking, and minimizing interfering signals. ADAPTIVE ARRAY ANTENNAS : ADAPTIVE ARRAY ANTENNAS Figure- Adaptive Array Coverage COMPARISION OF SWITCHED BEAM ANTENNA AND ADAPTIVE ARRAYS : COMPARISION OF SWITCHED BEAM ANTENNA AND ADAPTIVE ARRAYS SDMA(SPACE DIVISION MULTIPLE ACCESS : SDMA(SPACE DIVISION MULTIPLE ACCESS More than one user can be allocated to the same physical communications channel simultaneously in the same cell separated by angle only.
This is the next step in an evolutionary path toward increasing the capacity of cellular systems. SDMA(SPACE DIVISION MULTIPLE ACCESS : SDMA(SPACE DIVISION MULTIPLE ACCESS THE AIM OF SMART ANTENNA SYSTEM : THE AIM OF SMART ANTENNA SYSTEM To maximize the antenna gain in the desired direction
To minimize the gain in directions of interferers SMART ANTENNA VS OTHER ANTENNAS : SMART ANTENNA VS OTHER ANTENNAS They can null out interference from other nodes.
Contains an array of antennas elements and decide on which elements to receive signals (or transmit on) from and how much power to use on each element.
Spatial diversity. OVERVIEW OF SMART ANTENNA SYSTEM (SAS) FOR MOBILE COMMUNICATION : OVERVIEW OF SMART ANTENNA SYSTEM (SAS) FOR MOBILE COMMUNICATION SAS is equipped in base station (BS) with a pattern that is not fixed but adapts to the current radio conditions.
Traditional omni-directional or sectored antennas not only “Waste” power but also interfere to other users.
Smart antenna is a “Spatial Filter” that directs a beam toward desired user only.
It consists of a number of radiating elements, a combining/dividing network, a control unit (DSP). SMART ANTENNA USED TO OPTIMISE CDMA CAPCITY : SMART ANTENNA USED TO OPTIMISE CDMA CAPCITY Traffic load balancing
Handoff overhead management
Interference control TRAFFIC LOAD BALANCING : TRAFFIC LOAD BALANCING Load Balancing: SAS rotates sectors and changes beamwidth HANDOFF OVERHEAD MANAGEMENT : HANDOFF OVERHEAD MANAGEMENT INTERFERENCE CHALLENGES : INTERFERENCE CHALLENGES APPLICATION : APPLICATION cellular and wireless networks
electronic warfare (EWF) as a countermeasure to electronic jamming
satellite systems ADVANTAGES OF SMART ANTENNA : ADVANTAGES OF SMART ANTENNA Enhance coverage through Range extension
Improve building penetration and Hole filling
Reduce delay spread (time dispersion) because fewer scatters are illuminated
Reduce co-channel interference (CCI) and multiple access interference (MAI)
Link quality can be improved through multipath management
Improve system capacity
Helps to isolate the uplink signals from different users, reduce the power control burden CONCLUSION : CONCLUSION A smart antenna is a digital wireless communications antenna system that takes advantage of diversity effect at the source (transmitter), the destination (receiver), or both.
SAS can generate a set of “flexible” beams. In what follows, the pattern, beamwidth, and gain of each beam can be adjusted even adapted individually to optimize the capacity of a CDMA network.
Specifically, unlike the conventional scheme, no tower climbing and no physical changing of antenna orientation are needed. All the required sector orientation and beamwidths are software-controllable, remotely configurable. THANK YOU : THANK YOU THE END