CC1101-868MHz-800mtrs

[FL_KNV]

cc1101

Hello,
I want to use the CC1101 transceiver(module) with 868MHz frequency band for 800 meters. I have gone through the datasheet and it says output power limited only to +10db. I want to know whether it is possible to achieve 800 meters. Can the distance be increased by a directional antenna(but low cost is criteria). I am not an expert in RF designing so please help me.

 

[disisku_22]

cc1101 antenna

HI
With the 10dBm output power its not possible to achieve 800mtrs practically with the pcb antenna



There is only two way to achieve 800mtrs

As per theory 6dB increase in power double the range, so

1. Add external 5dB Power amplifier or
2. Use 6dBi gain antenna ( but it will be expensive ) its very difficult to get 6dBi gain either with the PCB antenna or Chip antenna

I think to get 800mtrs considering the loss in the environmental better to use external power amplifier

 

[vfone]

868 mhz power amplifier

Link budget analysis shall take in consideration not only the output power , distance, frequency and antenna gain, but also the receiver sensitivity for a given data rate.

 

[biff44]

cc1101 module

This part has one connection to the antenna. In other words, it has an internal sp2t switch to select transmit or receive functions. So just adding an amplifier to boost power will not work. You would have to have an external pair of sp2t switches and an amplifier that only worked when you were transmitting. It can be done, but it a little complicated.

If it is a fixed position system, I would go with the higher gain antenna. You can easily print a directional antenna onto the pwb, although it will be somewhat large.

 

[FvM]

cc1101 range

As an additional remark, the SRD regulations don't allow either a PA or a higher directivity antenna in this band. But the legal aspect may be irrelevant for a single application.

 

[biff44]

cc1101 power amplifier

Maybe, maybe not. If he is at 869.400-869.650 MHz, he should be able to use 500 mw ERP.

**broken link removed**

 

[FL_KNV]

cc1101 antena for

Thanks a lot guys for valuable information. I hope TI will post a reference design on website for 25mW or 500mW application for their chips.