Hi, I am currently working on a project using CC1101 (working at 915MHz range) to transfer data between two boards. I simply copied the reference design from CC1101 document with the 699MHz notch filter. I am using a SMD 868-960MHz antenna from Wurth Elecktronik (part number: 7488910092).
I am able to transfer data between two boards; however, the communication distance is really short. A 0dB transmission output power setting on the transmitter side could only gave me a communication distance of about 15cm, and +11dB output power could get me about 30cm. Any distance greater than 30cm will make them lost communication.
I used SmartRF along with CC1110 usb dongle to test the radio. It showed that the maximum signal strength (RSSI) I can get is about -70dBm (0dB output) and -50dBm (+11dB output). I also compared it with the TI Chronos Watch that easily gave me about -40dBm for 0dB output power.
Is there any key point I am missing in my design, like the layout of the circuit? Here is my design: U6 is CC1101, ANT1 is the antenna, and rest are the components from the reference design in between.
Thank you very much in advance!
Yang