Introduces timed arrays and design approaches to meet the newhigh performance standards The author concentrates on any aspect of an antenna array thatmust be viewed from a time perspective. The first chapters brieflyintroduce antenna arrays and explain the difference between phasedand timed arrays. Since timed arrays are designed for realistictime–varying signals and scenarios, the book also reviews widebandsignals, baseband and passband RF signals, polarization and signalbandwidth. Other topics covered include time domain, mutualcoupling, wideband elements, and dispersion. The author alsopresents a number of analog and digital beamforming networks forcreating and manipulating beams. The book concludes with anoverview of the methods to integrate time delay into the arraydesign and of several other adaptive arrays that prove useful inmany different systems. Examines RF signal concepts such as polarization and signalbandwidth and their applications to timed antenna arrays Covers arrays of point source, elements in timed antennaarrays, active electronically scanned array technology, and timedelay in corporate fed arrays Includes complete design examples for placing time delay inarrays Timed Arrays: Wideband and Time Varying Antenna Arrays iswritten for practicing engineers and scientists in wirelesscommunication, radar, and remote sensing as well as graduatestudents and professors interested in advanced antenna topics. INDICE: LIST OF FIGURES . PREFACE . 1 Timed and Phased Array Antennas . 1.1 Large Antennas . 1.2 Collection of Elements . 1.3 Overview of an Array Architecture . 1.4 Transient Vs. Steady State . 1.5 Time Vs. Phase . 1.6 Book Overview . 2 RF Signals . 2.1 The Carrier and Modulation . 2.2 Noise and Interference . 2.3 Polarization . 2.4 Signal Bandwidth . 3 Arrays of Point Sources . 3.1 Point Sources . 3.2 Far Field . 3.3 Array Sampling in the Time Domain . 3.4 Array Sampling in the Frequency Domain . 3.5 Grating Lobes: Spatial Aliasing . 3.6 Subarrays and Panels . 3.7 Electronic Beam Steering . 3.8 Amplitude Weighting . 3.8.1 Dolph–Chebyshev Taper . 3.8.2 Taylor Tapers . 3.8.3 Bayliss . 3.9 Thinned Arrays . 4 Elements in Timed Arrays . 4.1 Element Characteristics . 4.1.1 Polarization. . 4.1.2 Impedance. . 4.1.3 Phase center. . 4.1.4 Conformal. . 4.1.5 Size. . 4.1.6 Directivity . 4.1.7 Bandwidth. . 4.1.8 Balun. . 4.2 Elements . 4.2.1 Dipole Array . 4.2.2 Patch Array . 4.2.3 Spiral Array . 4.2.4 Helical Array . 4.2.5 Tapered Slot Antenna (TSA) Array . 4.2.6 Tightly Coupled Arrays . 4.2.7 Fragmented Arrays . 4.3 Mutual Coupling . 4.4 Element Dispersion . 4.5 Scaled Arrays . 4.6 Interleaved Arrays . 5 Array Beamforming . 5.1. PCB Transmission Lines . 5.2. S–parameters . 5.3. Matching Circuits . 5.4. Corporate Feeds . 5.5. Distributed Vs. Centralized Amplification . 5.6. Blass Matrix . 5.7. Butler Matrix . 5.8. Lenses . 5.9. Reflectarrays . 5.10. Digital Beamforming . 6 ActiveElectronically Scanned Array Technology . 6.1 Semiconductor Technology for T/R Modules . 6.2 T/R Module Layout . 6.3 Amplifiers . 6.4 Switches . 6.5 Phase Shifter . 6.6 Attenuators . 6.7 Limiter . 6.8 Circulator . 6.9 Correcting Errors Through Calibration and Compensation . 7 Time Delay in a Corporate Fed Array . 7.1 Pulse Dispersion . 7.2 Phased Array Bandwidth . 7.3 Time Delay Steering Calculations . 7.4 Time Delay Units . 7.5 Unit Cell Constraints . 7.6 Time Delay Bit Distribution at the Subarray Level . 8 Equation Chapter 1 Section 1Adaptive Arrays . 8.1 Signal Correlation Matrix . 8.2 Optimum Array Weights . 8.3 Adaptive Weighs without Inverting the Correlation Matrix . 8.4 Algorithms for Non–Digital Beamformers . 8.4.1 Partial Adaptive Nulling . 8.4.2 Adaptive Nulling with Weight Constraints . 8.5 Reconfigurable Arrays . 8.6 Reconfigurable Elements . 8.7 Time Modulated Arrays . 8.8 Adaptive Thinning . 8.9 Other Adaptive Array Alternatives . 8.9.1 Beam Switching . 8.9.2 Direction Finding . 8.9.3 Retrodirective Array . 8.9.4 MIMO
- ISBN: 978-1-118-86014-4
- Editorial: Wiley–Blackwell
- Encuadernacion: Cartoné
- Páginas: 224
- Fecha Publicación: 19/06/2015
- Nº Volúmenes: 1
- Idioma: Inglés