antenna range measurement with and without using network analyzer

i do not have a vna. what are my possible option to measure the various parameters of antenna (mainly gain and range and radiation pattern) of the antenna(it is patch antenna)

Without a VNA? You need something to excite, receive, and analyze signals.

If your frequency is low enough, you might be able to use an oscilloscope, but that would be one sizeable patch.

I'm no MacGyver, but I think you're out of luck.

Other options are generator plus spectrum analyzer, test receiver or sensitive level meter.

Spectrum analyser with tracking generator works well too.

I do this all the time. Get a pair of known gain antennas. Point them at each other at your distance of interest (like 10 feet, 30 feet, whatever). Drive one of them with 10 dBm power level at the frequency of interest. Go to the other side and measure the received power. This is your "calibration"

then replace the first antenna/source with your device under test. sweep the DUT around in azimuth and altitude, and record the received power. Subtract out your source calibrated gain, and you have the gain in dBi vs azimuth and elevation.

It does help if you have a cheap antenna rotator, like they use for TV antennas, to move the DUT around. the one I have uses a wireless handheld remote to move it around, which eliminates the rotor control wires as a possible reflection/re-radiation source.

If possible, run the DUT off of batteries with very short wires

I have some plastic hinged holders that can change the DUT elevation manually.

I uses a lab signal generator and portable spectrum analyzer to do the above. But if you want to do this cheaply, get a 5V VCO and tune it with a potentiometer, and for the receiver you could use an analog devices log amp detector and measure the Vout.

dear biff44,
great idea! i just have few questions. i have a VNA but dont have rotator and a anechohic chamber.

what is the part number of your rotator? how do you handle reflected waves from the object around? do you have anechohic chamber or is the anyway to do this cost effectively?

why do we one pair of known gain antenna?
if i know one antenna gain. can i not use friss transmission equation and find out the gain of my antenna

because Friis equation sux at accurately predicting propagation in the real world. You would have many dB's of error.

http://www.amazon.com/Channel-Master...ntenna+rotator

use a pvc pipe out the top to hold your DUT.

and technically speaking, you only need to pre-know the transmitting antenna gain. The receiving antenna gain is not important as you just swap out the transmitting antenna with the DUT and see the difference in received power.

i have a printed antenna whose radiation pattern and polarization is needed to be measured. i am using a network analyzer. can someone tell me how it can be done.

I believe the necessary tools have been already mentioned in your previous thread, I merged your new post as you are continuing the same topic.

Besides choosing a suitable measurement antenna, you need to think about feed line isolation, otherwise the radiation diagram might be very different from the final device.