What are the benefits of an LCP (liquid crystal polymer) type antenna in a smartphone? Is it good in terms of signal reception?

My answer will be a bit roundabout so apologies in advance. It may seem off topic but it will provide background for the actual question. Also I'm not a material science expert and only have second hand knowledge of both ceramics and LCP.

Signal strength is one of the most important qualities to consider when designing an antenna both transmitting and receiving. But it's not the only one. Other factors like

Ease of construction, installation and maintenance

Environment in which the antenna operates

The function it has to perform

are just as relevant.

It is important to stress on the third point because of something called reciprocity principal of antennas

It states that properties governing transmission and reception are the same for an antenna. If the antenna is a good transmitter for a particular situation, it is also a good receiver.

If we look only at signal strength then nothing can beat parabolic antennas. They are so powerful that they can communicate with satellites thousands of KMs away.

But a parabolic antenna can't be made to fit inside a mobile phone. Even if they could, their highly directive nature will not be suitable for mobile communication. We want antennas that create coverage in a 3D space, not just a straight line.

And so while mobile phone antennas are decent receivers you can't really replace the antenna on towers with mobile phone chips. [You kind of can with reflectors but it's not the same thing even then]

Reciprocity principle holds, but it can't surmount design constraints. We need different antennas to serve different purposes.

In mobile phones we use dielectrics that are made of the same materials as the rest of the chips. Leading to a more compact design.

Some helpful links on the subject

https://www.globalspec.com/learnmore/semiconductors/communication_ic/chip_antenna

https://www.microwavejournal.com/blogs/1-rog-blog/post/18190-picking-pcb-material-for-a-patch-antenna

https://electronics.stackexchange.com/questions/243341/how-does-a-chip-antenna-work/244435#244435

>”Technically, they are cavity resonators where the cavity between conductive surfaces is filled by a ceramic core.”

Now coming to LCP it has a low dielectric constant this property can allow it to create radio waves like ceramic materials that are used today.

The key advantage that it possesses over ceramics is its flexibility,it can be bent and rolled therefore easily attached to pcbs in any form.

It can perform over frequencies as high as 100 GHz.

https://ieeexplore.ieee.org/document/1284807

On the flip side, as you move towards higher frequencies antennas become so small that advantages offered by dielectrics are lost. At these frequencies the copper base will perform just as well as LCP,if not better.

[At high frequencies loss in dielectrics is due to power radiated out into the free space whereas loss in metallic antennas is due to conversion of electrical signal into heat because of skin effects.]

LCP is preferred for its range. In a more compact form it can support a wide range of frequencies. Especially the ones needed in, you guessed it, 5G.

References

- Best materials for mm wave

https://www.microwavejournal.com/blogs/1-rog-blog/post/27798-what-type-of-circuit-material-works-best-for-millimeter-waves

- copper conductivity at mm wave

https://ieeexplore.ieee.org/document/6768175

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