Low-noise Amplifier for a sensitive radio receiver

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When designing a low-noise amplifier (LNA) for a sensitive radio receiver, key noise sources to consider include thermal noise, shot noise, and flicker noise at the transistor level. Different LNA topologies, such as common-source, common-gate, and common-drain with inductive degeneration, significantly affect the overall noise figure and gain. Trade-offs in optimizing these parameters involve balancing noise performance with gain and stability. The discussion also highlights the importance of isolating radio circuits on PCBAs to prevent noise coupling, particularly when digital electronics are present. Understanding receiver sensitivity and employing techniques like "Star Grounding" can enhance the design's effectiveness.
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I'm designing a low-noise amplifier (LNA) for a sensitive radio receiver. What are the key noise sources I need to consider at the transistor level (e.g., thermal noise, shot noise, flicker noise)? How do different LNA topologies (e.g., common-source, common-gate, common-drain with inductive degeneration) impact the overall noise figure and gain? What are the trade-offs involved in optimizing these parameters?
 
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In addition to the buy-vs-build question asked by @Baluncore -- do you have experience designing PCBAs with sensitive radio circuits? What is the application? Will there be digital electronics on the same PCBA? It is *extremely* important to isolate different parts of radio circuits on PCBAs to avoid coupling of noise between sections via shared impedances (like power supply and ground impedance). Are you familiar with techniques such as "Star Grounding" to achieve such isolation?

Also, what level of receiver sensitivity (in dBm) are you shooting for? https://www.repeater-builder.com/tech-info/measuring-sensitivity/measuring-sensitivity.html
 
I was wondering why you have chosen inductive degeneration for common source operation?
 
It’s all about matching the source impedance to the transistor input impedance that optimizes its noise figure. Pay attention to the Smith chart noise figure circles on the device data sheet.
 
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