CC1352P: SMA Antenna performance issue

Do you have a spectrum analyzer enabling you to check the conducted performance? Meaning if you connect a spectrum analyzer to the SMA, set the chip to send a CW and measure the output power. 

Dear TER,
Thanks for your reply...
Unfortunately we don't have an RF Analyzer with us.

Can you suggest some another steps for the same or some another kind of antenna that is recommended...

The antenna you have selected looks good based on the link so It's most likely not an issue here. 

You need some basic RF equipment to debug this since it could easily be that the soldering causes a loss.  

This antenna which I used I think is Monopole antenna. Do you think it will effect the performance also its a 5dBi antenna. We have sensors placed below our Launchpad 1m apart from each other and are 4 in quantity. 

Do you think buying a 2dBi dipole antenna will give better performance.

Please have a look at this pic which I found on internet.

An antenna with a high gain will be more directive and hence the total performance will be dependent on how the antennas are placed relative to each other.

With a 5 dBi antenna you will get better performance if the antennas are places correctly compared to 2 dBi antennas but if the placement/ direction is not optimal the loss will larger. 

Hence if you have control over how the antennas are placed relative to each other you can use high gain, if not, use lower gain. 

Thank You TER 

Do you think Using External Patch antenna will solve the issue instead of using Whip antenna as I was testing using Whip antenna.
Distance is 1m from center as can be seen. I asked for 2 dBi because our sensors are placed all in 360 degree.

With 1 m, do you have metal from the Vehicle in between or is it line of sight? 

I need to know if this is a bad connection issue or placement of sensors within a car issue. 

Hello TER,

Yes We have metal. Its placed on the bottom of car chassis. All sensors are perfectly tuned.
As this is a car would you suggest some another antenna.

I have to check with a different group on this since they have worked more with cars and the placement of antennas in them. 

Thanks TER
I will wait for the same...

Sorry for the delay, people has been out a few days.

The feedback I got is that we don't have any strict recommendation for  antenna placement and antenna type. The optimal placement will be dependent on the type and size of the vehicle  and the RSSI accuracy requirements etc. For some vehicles more than 4 nodes may be required to get the wanted coverage/ accuracy. 

For the type of antenna we generally recommend to use the inverted F antenna we use on our Launchpads (small, cheap, good efficiency) but other types are used based on preference and  the system they want to fit the antenna into. 

I would assume that based on the placement etc both more or less antenna gain could be an advantage. For car access a node will not be able to receive in some angles due to metal etc and therefore it's not an advantage to have gain in this direction.