Antenna Design Frequently Asked Questions
Ask the Expert
Symmetry Electronics is an industry-leading distributor of wireless connectivity solutions. Our team of Applications Engineers provide best-in-class technical support and are available to help navigate you to your ideal antenna solution. Our knowledgeable Applications Engineer, Augustine Nguyen, is answering your most frequently asked questions about internal and external antenna designs.
1. Do more expensive antennas work better?
Price doesn’t necessarily equate to quality when it comes to antenna design. While external antennas (i.e. whip antennas) are generally more expensive than their internal counterparts because of their size. There are additional material costs associated with external antenna manufacturing. However, the higher price point of external antennas does not mean that they function better than internal antennas. Antenna selection is ultimately dependent on its application requirements.
2. What are some of the most common causes of weak antenna signals?
Weak antenna signal could be caused by a wide range of issues. Some of the most common causes for weak signal include:
- Improper tuning
- Poor enclosure design
- Inhibited line-of-sight (LOS)
- Environments with increased RF interference. Developers can mitigate signal
3. How do you check an antenna's signal strength?
An antenna’s signal strength can be measured by testing its radiation performance in an RF anechoic chamber. Radiated performance measurement tests are administered by antenna suppliers or engineering design services (EDS) firms. Laird Connectivity offers comprehensive EMC testing services. Kyocera-AVX also has an automotive anechoic test chamber that is capable of testing devices from 600 MHz to 6 GHz. Additionally, Connected Development is one of the EDS companies within the Exponential Technology Group (XTG), and has their own in-house anechoic chamber capable of conducting a variety of wireless test and measurement services.
4. Do all antennas need to be tuned?
Yes, all antennas are tuned in order to be resonant at specific frequency bands depending on the supported wireless protocol to be supported. For example, antennas are tuned to 2.4 GHz for Bluetooth Low Energy (BLE) and Zigbee. Antennas using LoRa as their supported wireless protocol are tuned to 868/915 MHz.
5. Does the size of an antenna affect signal strength and range?
Generally, the size of an antenna indicates its dBi gain, or directivity. Larger antennas will have a higher dBi gain, whereas smaller antennas will have lower gain with a more omnidirectional radiation pattern.