How to increase range of transmission?

Hi Leila,

Can you please provide more information:

1. Whether you're using TI's Zstack, or some other stack (MAC, NWK...)?
2. What are the desirable ranges of the network you'r planning?

I can suggest two common solutions to extend the coverage zone of your ZigBee network:

1. Additional hardware; transmission range can be extended by adding the cc2591 RF Front End.
2. You might consider adding routers to your network, which can extend network's coverage
   zone and number of ZigBee End Devices in the network (if you'r using Zstak).

Br,

Igor

Hi Igor,

Thanks for the response. I am not using Zstack right now. How should I migrate from my current code to Zstack? our desirable range is around 500 ft. do you have any suggestion for router? 

Thanks a lot

Leila

If you don't need Z-Stack, a simpler approach might be the SimpliciTI stack (www.ti.com/simpliciti).  It can work with the CC253x parts and has built in range extender support.

Jim Noxon

Hi Leila,

You should probably deciding first what is the stack you'll be using for your application.

Migration issues and suggestions regarding the router may be very different from stack to stack.

Br,

Igor 

Hi Jim,

I am not sure what is the best approach either Zstack or SimpliciTI stack or some thing else, as Igor suggests I need to choose a stack which is suitable for long range communication and it is low power for high data rate (the system should only  run on batteries). Please let me know what you guys think?

Thanks,

Leila

SimpliciTI can work on the so called proprietary radios whereas Z-Stack cannot.  The 802.15.4 radios are constrained to 250kbps data rates always.  The proprietary radios can go to 500kbps and some can do 600kbps in QPSK modulation mode.  The radios all use about the same amount of transmit power so the max distance is somewhat fixed due to the physics of the RF signal rather than the protocol used.  Also, SimpliciTI can operate on radios which work in the sub 1GHz bands and you gain distance using lower frequencies purely due to the physics of the RF as well so if you are looking to maximize your distance for each milliwatt of power, going lower in RF frequency is a definite option you should consider.

To truly answer your question, you need to setup a power budget to model the power used on an average basis.  This budget should reflect the amount of time you intend on communicating and the amount of power the radio requires during communications.  You can use the Friis equation to determine what certain power levels will provide you for distance as well as frequency bands.  Then you need to compare these values with the total amount of power your battery can deliver and still maintain enough voltage to operate your system (its not the same as the mAh rating on the battery) to see if you can achieve your design goals.  This same model can be used to determine the number and distances any repeater nodes you will need.

Jim Noxon

Hi Jim,

Does that mean that the Z-stack does not support the sub 1GHz bands.

Hi,

I have decided to use Zstack, however I have already an application  which uses basic RF functions,. I read the Zstack user's guide but have no clue how to modify my current code. Which documents can be helpful to speed up migration from basic communication to Zstack?

Thanks in advance,

Leila

Hi Leila,

The best way is to install the Zstack and run one the sample projects

provided with it.

Try to understand how these projects works (in a brief way) and then try

to modify existing code and finally implement your application/s.

In case you stuck, post questions in this forum.

Br,

Igor.