In this chapter we will discuss theoretical models for characterising slots in waveguides. in Chapter 4 we looked at basic theories for slot apertures and found expressions for the conductance of longitudinal slots in rectangular waveguides. We will now look at ways of finding the slot susceptance, the effect of slot offset on resonance conditions, influence of wall thickness, waveguide dimensions, etc. We will demonstrate how electromagnetic models can tell us about slot behaviour in greater detail. The longitudinal slot and the transverse slot in the broad wall of a rectangular waveguide will be treated in. particular. We will thus establish a basis for an efficient design process of high-performance slotted waveguide arrays.

Chapter Contents:

• 5.1 Modelling principles
• 5.1.1 Using experimental data
• 5.1.2 Equivalent circuit approach
• 5.1.3 Electromagnetic models
• 5.1.3.1 The boundary problem
• 5.1.3.2 Zero wall thickness
• 5.1.3.3 Choice of basis and testing functions
• 5.1.3.4 The other slot problems in Figure 5.5
• 5.1.4 Finite wall thickness
• 5.2 Integral equation solution
• 5.2.1 The internal field
• 5.2.2 The external field
• 5.2.3 Matrix elements
• 5.2.3.1 Internal field contribution
• 5.2.3.2 External field contribution
• 5.2.3.3 Excitation vector
• 5.3 Longitudinal slot characteristics
• 5.3.1 Slot electric field distribution
• 5.3.2 Slot magnetic field distribution
• 5.3.3 Experimental verification
• 5.3.4 Weakly excited slots
• 5.4 Transverse slots
• 5.4.1 Introduction
• 5.4.2 Theoretical analysis
• 5.4.3 Results
• References

Inspec keywords: antenna theory; slot antenna arrays; aperture antennas; rectangular waveguides

Other keywords: longitudinal slot conductance; high-performance slotted waveguide arrays; slot behaviour; slot susceptance; wall thickness; waveguide dimensions; slot apertures; rectangular waveguides; transverse slot; resonance conditions; slot offset effect; slot models; electromagnetic models

Subjects: Waveguides and microwave transmission lines; Antenna arrays; Antenna theory