Telecommunication technologies

MINISTRY OF HIGHER AND SECONDARY SPECIAL EDUCATION OF THE REPUBLIC OF UZBEKISTAN
MINISTRY FOR THE DEVELOPMENT OF INFORMATION TECHNOLOGIES AND COMMUNICATIONS OF THE REPUBLIC OF UZBEKISTAN
SAMARKAND BRANCH OF TASHKENT UNIVERSITY OF INFORMATION TECHNOLOGIES NAMED AFTER MUHAMMAD AL-KHOREZMI
FACULTY OF "TELECOMMUNICATION TECHNOLOGIES"

Independent work №4


By subject «Electromagnetic fields and waves»
By topic: « Study of the elements of waveguide paths»

Performed by: Student TT-2106 group Kutlimuratov N.
Has accepted: Christo Ananth

Samarkand 2022-2023
Plan:

1. 
   Introduction
   
2. 
   Description
   
3. 
   Concept
   
4. 
   Diagram
   
5. 
   Equation
   
6. 
   Derivation
   
7. 
   Conclusion
   

Introduction
Waveguides are hollow metallic tubes that are used to guide electromagnetic waves at high frequencies. Waveguide paths are used in various applications such as antennas, filters, and couplers. This paper aims to investigate the elements of waveguide paths and their properties.
On the single-mode waveguide arms, the change of refractive index is translated to the optical phase change only. The cascaded systems can be well-represented by a set of analytical equations or a linear transfer matrix, and the required settings to reach the target output can then be readily calculated. However, there remain two problems. For one, the cascaded structure requires a large number of independent tuning units, which may pose a challenge for electronic wiring during integration and assembly Secondly, the phase tuning on a single-mode waveguide cannot efficiently introduce variable attenuation of light amplitude. In fact, the MZI and DC-based solutions all work under the theoretically lossless condition apart from the insertion loss in practice, i.e., if the power of one output is tuned down, the sum of the output power from the remaining ports is bound to go up.
To illustrate the second problem, let us consider the integrated power splitters, a fundamental PIC component that divides the input optical power into multiple streams. They can be realized by Y-branch structures, directional couplers (DC), and QR code-like nanostructure. However, they often perform a fixed splitting ratio, as shown in a. The tunable power splitters can be realized by the cascaded MZI-based device, as shown in. By precisely tuning each phase shifter, the input light can be divided into arbitrary splitting ratios at the outputs. Note that in the phase tuning does not affect the overall power passing through the device. To implement extra attenuation, each output port needs to connect to a variable optical attenuator (VOA). The extra VOAs require more independent tuning elements plus methods to suppress the crosstalk among them, thereby increasing the device footprint and cost.


Description:
A waveguide path is a structure that consists of a series of waveguide elements. These elements include straight sections, bends, and transitions. Straight sections are used to propagate the electromagnetic waves in a straight path, while bends are used to change the direction of the waves. Transitions are used to connect different types of waveguides or to change the cross-sectional shape of the waveguide.