1. H

    GNSS Receiver designed IC circuit noise issues

    Hello everyone I wanted to share with you the design of a 2-layer full GNSS board that I have recently developed using Direct RF sampling architecture. The board consists of several blocks, each equipped with SMA input/output connectors, as well as an SMA connection between VCC and GND to check...
  2. B

    How to match ceramic antenna to GPS chip

    Hi, Current project is to move from a 1/4 wave whip antenna to a ceramic chip type (e.g. Johanson 1575AT43A0040). I have a pi matching network on the pcb and can look 'into' the antenna with my vector network analyser and get the conjugate impedance. I have tried to simply match that to 50...
  3. E

    Designing PCB with multiple RF circuits

    I need Tips and recommendations on how to design a PCB with multiple RF circuits. In my case, the PCB includes a GPS receiver, 802.15.4 2.4GHz, and 433 MHz transceivers. I plan to use a GPS module with a patch antenna. The 433 MHz transceivers will have a PCB or ceramic antenna. an external...
  4. H

    GPS receivers Front-End Design Problems

    I am designing a GPS L1(PWR=-160dBW) band Direct RF sampling receiver and the front-end: (passive antenna + LNA(21dB) + BGA1(30dB) + jumper + BPF(L1(fc=1575.42MHz,BW=15MHZ) + BGA2 (30dB) + BGA3(30dB) + VGA(-13.5 to +18 Gain Control in 0.5 dB Steps) ). all amplifiers are supplied with a +5 V...
  5. K

    LNA simulation result doesn't match data sheet gain

    Please can you explain to me why the "Simulate ONLINE - BGA524N6 - Low noise Amplifier for GNSS Applications in 1550 MHz - 1615MHz with a High Q Inductor for Matching (Vcc = 2.8 V)" doesn't match the High insertion power gain: 19.6 dB. The simulation shows 10.16 dB only for 1.46 GHz.
  6. S

    STM32F4 - Radiolink SE100 GPS

    Hi. I am using STM32F407VGT6 this one and RadioLink SE100 GPS. I am trying to get $GNGGA data via USART and displaying it in putty terminal. I am able to get and print data. After 3-4 minutes gps sensor led is blinking but no data is printed on terminal. /* USER CODE BEGIN Header */ /**...
  7. S

    Controll drone by a laptop

    Im currently building my own drone and I was wondering, if I could controll it with a laptop rather than an RC Transmitter, because I mainly want it to fly autonomously. Could I f.ex. just buy an FrSky receiver and control it with a laptop? And if I want to change the waypoints while the drone...
  8. O

    Sending phone's GPS data to microcomputer

    Hi. So I'm doing a project where I'm using a Jetson Nano 2GB as my main PC. I want to get my GPS position through my Android phone's GPS and be able to put it in a csv file in the Jetson. I've made a research in the internet and saw many few things, but I don't think it was helpful. Anyone...
  9. I

    TTGO V1 no GPS signal

    Hey Folks, I am encountering the following problem. I have a TTGo board V1 and i tried compiling this code on it #include <TinyGPS++.h> #include <axp20x.h> TinyGPSPlus gps; HardwareSerial GPS(1); AXP20X_Class axp; void setup() { Serial.begin(115200); Wire.begin(21, 22)...