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May 26, 2009 Resouces
Circuit Design, Inc. Newsletter
In this issue

RF Technical Resources

RF design guide
These documents are offered as guidance for users who intend to design radio systems using RF radio modules.
We hope this information will help you to develop an attractive product.

Cal culation tools - Free -
Calculate propagation loss - Clic k
Calculate electric field intensity and received power - Clic k

T echnical literature
Compare wide and narrow band modules - Click
Learn about Fresnel zone and hight patterns - Cl ick


Quick Links

In this issue, we present links to useful resources.

Frequently Asked Questions


Q. How can I distinguish received data from noise? A. Use the RSSI signal. It is difficult to determine whether you are receiving data or noise only using the signal from the DO. The DC voltage of the RSSI indicates received signal strength. The RSSI level can be monitored using a single-chip CPU equipped with an AD converter. If you set the RSSI threshold level for distinguishing signal from noise, when the RSSI level is higher than the threshold, the DO output is real data.

Q. There is a problem with communication range. What is the problem? What should be checked?
A. The possible causes are:

  • * The position of the antenna
  • * Interference from other equipment

  • Please check RSSI output.

Q. What is multipath fading? What is a dead spot? A. The radio waves emitted from the transmitter follow various paths as they disperse towards the antenna of the receiver. Multipath fading occurs due to the combination of waves that arrive directly from the transmitter to the receiver, and waves that arrive after being reflected off walls, ceilings, terrain and other obstacles. - More

Circuit Design's Anechoic chamber

Circuit Design's EMI 3M anechoic chanber is suitable for EMI & EMC testing, as well as for high precision measurement of the radiated electromagnetic field emitted by antennas of all types of radio equipment.

Recruiting distributors

Circuit Design is looking for distributors in Hungary and Greece.

If you are interested in joining our distributors, please contact us

phone: +81263821024

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