Reading materiel for microwave project - Page 1
Forum section: electronics / rf-microwave

author: hamster_nz
author_rank: Super Contributor
timestamp: July 31, 2017, 05:32:52 am
content: This will be my first microwave project. I want to design a 1575.42 MHz amplifier, to take the signal from an active GPS antenna and boost it to the point I can capture it using an FPGA SERDES/transceiver, to experiment with carrier phase GPS.What reading material should I start with?

author: DaJMasta
author_rank: Super Contributor
timestamp: July 31, 2017, 06:18:09 am
content: For a specific project like this, I always learn best by seeing the application and then learning why things are the way they are, so I would start with some schematics (or at least block diagrams) for GPS receivers and some information on the GPS signal standard itself.GPS signal is very low level, so you'll be getting amplifiers and filters and it's high frequency so you'll need to downcovert at least once before you can sample it... but it's also very well understood and documented. Look around for some DIY GPS frontend projects, take a look at some well fleshed out datasheets with block diagrams for their GPS systems, and then maybe pick up and take apart a cheap active antenna.Videos could also be a good option to get an idea of how mixers and these sort of RF-specific components work, and there's a number of people on the forums with tutorials of various sorts. Just on the last page of this forum I came across w2aew's videos and they cover a lot of the basics of how primary building blocks work and demonstrating them on the bench, but from the opposite approach and another excellent resource would be Shahriar's videos on TheSignalPath - in taking apart, fixing, or examining RF gear, he goes through how they operate and demonstrates them in experiments - a more top-down approach to learning about things, but it's full of great insight.There are many resources available and many approaches depending on how you like to learn. I'd say that for this application, if you have access to a spectrum analyzer, it would be really helpful in evaluating the circuit as you design it, though it's probably not useful in the early planning steps.

author: hamster_nz
author_rank: Super Contributor
timestamp: July 31, 2017, 07:05:52 am
content: Quote from: DaJMasta on July 31, 2017, 06:18:09 amThanks for the ideas!I've had a bit of experience with GPS signal, and have written a working receiver using a Skyworks SE4150L front end (no, I didn't design the board, but I did solder onto the test points)So I am really interested in working towards the higher level of accuracy that carrier phase can give.

author: jmsigler
author_rank: Regular Contributor
timestamp: August 02, 2017, 03:02:44 pm
content: There are a couple books on the front end that have schematics likeFundamentals of GPS Receivers: A Hardware Approach, which could be useful. Otherwise it is more about just calculating how much gain you'll need and adding amplifiers. I would look into best layout practices to keep amps isolated and stop feedback. I assume you want to use the serdes because its a relatively cheep 1 bit adc?Keep me updated on this project, I'm working on a zynq based receiver for the MAX2769, but its still in the early stages.

author: GreggD
author_rank: Regular Contributor
timestamp: August 02, 2017, 03:13:24 pm
content: This is a great presentation on low noise amplifier design.There are four videos on this page. We should have to pay money for this level of teaching but it is free.http://rickettslab.org/bits2waves/design/low-noise-amplifier-design/