Title: Design and Development of D-band Low Noise Amplifier for Military and Surveillance Applications
Block diagram is attached
schematics of the critical circuit core:
Schematics are attached
Target performance summary table:
The proposed design of LNA is targeted to the following specifications.
The major steps in this work plan are
Finally, the Graphic Database System (GDS) file will be created and this can be used for IC fabrication.
Short description of the circuit and your specific design goals:
Following are the different stages to consider in developing the proposed design.
Choice of devices and bias circuit design:
The research initially starts with selecting the best device/transistor to define the amplifier topology which best suits the design requirements. As this is a high-frequency design, the parameters like scattering and Maximum Available Gain to considered carefully. These parameters allow a first feasibility analysis of the design with a specific transistor. Then the bias operating point is to be chosen to ensure that to maintain the isolation of the RF stage. Current mirror technique will be used in determining bias operating point.
Evaluating of Stability, Maximum Available Gain, S-parameters and Noise Figure:
The conditions of stability of the transistor will be taken care in this stage to avoid possible oscillations. Then, the selection process of the operating point will starts according to the intersection between the constant gain circles and the noise figure circles, with better S-parameters to find out the points at which they are best satisfied with required specifications. The systematic analysis of the design requirements is carried out in terms of impedance matching at the input and output of the amplifier. After this, the values of the reflection coefficients at the input and the output will be considered to design LNA with their corresponding input and output matching couplers.
Simulation and Layout design of LNA
The designed LNA architectures will be simulated to verify its functionality and later will be analyzed using Layout and parasitic extractions. EM simulation of LNA will be carried out for final LNA architecture design to verify all required parametric analysis and also, co-simulation of the schematic with the EM response will be carried out. To achieve the required gain cascading may be done based on the obtained results.
The expected outcome of the research
Technical novelty and utility
In today’s world, the development of Millimetre-wave technology has been accelerated for security check-in in recent decades due to its ability of imaging the non-metallic explosive or weapons under the clothes of a human being without intrusive detection. Millimetre-wave receivers as a class are an essential part of every Millimetre wave-based subsystem, particularly radiometers, radar, and radios. However, several applications use a highly sensitive Millimetre-wave receiver to achieve the ultimate primary function of the system. However, the equivalent power of a received signal is too small to be discriminated from the noise by the detector. Detection of this weak signal possesses strict requirements on the sensitivity of the receiver. So, the first block in the Radio Frequency (RF) system is a Low Noise Amplifier (LNA) which plays a critical role to boost the received weak signal to above the intrinsic noise power. Thus, the entire performance of the receiver is purely dependent on high-performance LNA. In military and surveillance applications, it is necessary to achieve better spatial resolution and more compact scanners, increasing the frequency above 100 GHz is required. So, based on the current research going on across the globe it is observed that most of the research is focused on D-Band which is typically in the range of 110-150GHz.However, the bandwidth of the system is chosen based on the application. This project is primarily focusing on millimetric wave imaging for which frequency is chosen at 140GHz. The objectives are · To design an architecture for a Low Noise Amplifier with better noise performance, Stability, Power Gain and Bandwidth at 140GHz. · To simulate and verify the functionality of the designed LNA at 140GHz. · To design an LNA with Low power dissipation and High speed. · To create a Graphic Database System (GDS) file for the designed LNA.