PHASESHIFTER Submitted by : Vinay Kumar singh EC – F 090973116
Contents1. INTRODUCTION2. TYPES OF PHASE SHIFTER.3. APPLICATIONS.4. CONCLUSION.
INTRODUCTION•A Phase Shifter is two-port device whose basic function isto provide a change in the phase of RF signal withpractically negligible attenuation.
CLASSIFICATION OF ANALOG PHASE SHIFTERS Analog Phase ShiftersFerrite Semiconductor
FERRITE PHASE SHIFTERS• THEORY » Is the change in the effective permanent of ferrite with the magnetic field As the permeability increase the effectiveness of the ferrite rod increases since guided wavelength is equal to wavelength in space divided by effectiveness (permeability), hence guide wavelength decreases, which result in a change or RF insertion phase.
Semiconductor Phase Shifters Planar/hybrid MIC Monolithic Reciprocal Non reciprocal Reciprocal Non reciprocalP-I-N GaAs FET GaAs FET GaAs FET GaAs FETdiode (Passive) (active switch) (passive) (active switch) • Switched line • Switched path • Switched • Switched path • Hybrid coupled line/loaded DGFET • Loaded line line • High-pass low- • Hybrid coupled pass • High-pass low • Switched -pass network
DIGITAL PHASE SHIFTER Specification of Digital Phase ShifterFrequency 0.5 to 2.0 GHzPhase Accuracy +/- 10Amplitude Balance +/- 1.0 dBV.S.W.R 1.7:1Noise Figure 7 dB 0 dBm CW ~ +2- dBmInput power MaxSize 4.95 x 3.38 x 1.0 inchSwitching Speed 500 nSec
Basic terms connected to antenna array :1.Insertion phase - It is the phase delay experienced by the RF signal between its input and outputs ports.2. Input VSWR - The input voltage standing wave ratio is defined as VSWR = 1 + | S11 | 1 - | S11 |3.Directivity - The ratio of the radiation intensity in a given direction from the antenna to the radiation intensity averaged over all directions D = 4 U / P rad
APPLICATIONS• Used in a variety of communication and radar systems• microwave instrumentation and measurement systems• In industrial applications.
CONCLUSION• Phased array radars are used for inertia less scanning and tracking. They as well can be used for multi target tracking.• Phased arrays can also be used for air traffic control at the airports.• Other than defence applications, phase shifters are finding their place in routine life.• An American company is working on a project where phased arrays are used for finding the blind stops on road while driving.• With such high tech commercial application, driving on road will be safer.• The phase shifter technology for phased arrays has no limitation either in defence applications or in our daily life.