There are generally 3 types of antenna that a system engineer should know for low power wireless design usually found in consumer electronics product. PCB, wire, and chip antenna. For simple RF transmission in the ISM band, these antenna should be sufficient to build a working product.
Basic principle of Radiation
Antenna radiates and receives EM waves based on the principle of resonance. In short, when the transmit or receive EM waves oscillates in accordance with the resonance frequency of the antenna, EM waves can be emitted or picked up by Antenna effectively.
Monopole and dipole are generally common omnidirectional antenna used on consumer electronics. The reason is that for short range connectivity device, the access points can be anywhere in the room.
Types of Antenna and application
PCB patch antenna: it uses PCB micro-strip patch to create mono-pole omnidirectional antenna
PIFA antenna: it's special type of PCB antenna where required antenna area is smaller.
The goal is to choose the right antenna for the design base on space, performance, and cost constraints.
- cheap to design
- takes a board space
- special design knowledge required
- one would often seen PCB antenna on small devices such a remote control, headphones, etc.
- best performance
- large space required
- need specific antenna design knowledge
- one would see from a medium electronics such as a radio, set top box.
- small footprint
- easily to integrate
- not the best performance
Application: small electronics such as remote control.
Summary and Conclusion
- Pros and cons of PCB, wire, and chip antenna is a trade off between cost and performance
- Monopole and dipole antenna has omni-directional radiation pattern needed for consumer electronics.
1/4 wave monopole and 1/2 wave dipole are generally common omni-directional antenna used on consumer electronics. Omni-directional reception and radiation is needed for the antenna to pick up signals from all directions because the wireless router or cellular tower can be in any direction with respect to the wireless product
The main job of an designer is to understand the characteristics of antenna and balance between cost, size, and performance for the product.