Feeling stupid for not considering the whole scope of wireless when responding the first time. You all covered ti pretty well. My mind read "What is difference between wifi and wireless internet"

 

Wireless is normally considered to be transmitting a signal through free air using electromagnetic waves.
Including a power transformer in that category, which transmits a signal by magnetic induction through a close-coupled magnetic core, is really stretching it.

 

What is difference between wifi and wireless Do both mean different or same? It looks like both are the same. What do you think ?

Today, these terms are generally used in the context of voice, video and data communications. The term "wireless", used in this context, is a generic term to describe communications between remote points without the use of interconnecting wires.

WIFI is a specific set of wireless standards. Devices designed to these standards can communicate with each other.

 

This is what wireless looked like:

View attachment 213126

Where did you get the picture of me keying out?
Max.

 

Where did you get the picture of me keying out?
Max.

Is that really you?

Once I was touring an HMS with our 6th form. I came up behind the wireless operator operating the keys. As I was the group photographer documenting the tour I took a photo from behind. When the flash when off he jumped off his chair and nearly bumped his head on the racks above.

 

Where did you get the picture of me keying out?

I didn't think you were that ancient...

 

Is that really you?

Not quite, but this is, somewhere in the Libyan desert.

Max.

 

Wireless is normally considered to be transmitting a signal through free air using electromagnetic waves.
Including a power transformer in that category, which transmits a signal by magnetic induction through a close-coupled magnetic core, is really stretching it.

I ask again? What's the stretch? Physics or common usage? There seems to be a huge blind spot called power isolation transformers engineered specifically for their wireless galvanic isolation properties.
https://www.allaboutcircuits.com/technical-articles/galvanic-isolation-purpose-and-methodologies/

1:30

The common definition of Wireless Power Device by magnetic induction with coils of wire is inclusive of a power transformer. All other magnetically coupled technologies are an attempt to match the efficiency of close-coupled magnetic core versions.

 

Wi-Fi acronym stands for Wireless Fidelity.

A take -off from the old days of HiFi (High Fidelity terms used for properly reproduced audio/music)

 

there are so many documents, Will you recommend any good documents to understand the WIFI protocol ?

You're confusing 2 things due to lack of understanding. Underlying TCP/IP protocol and the radio-link method to carry that traffic wirelessly at 2.4GHz or faster.

 

I ask again? What's the stretch? Physics or common usage? There seems to be a huge blind spot called power isolation transformers engineered specifically for their wireless galvanic isolation properties.
https://www.allaboutcircuits.com/technical-articles/galvanic-isolation-purpose-and-methodologies/

1:30

The common definition of Wireless Power Device by magnetic induction with coils of wire is inclusive of a power transformer. All other magnetically coupled technologies are an attempt to match the efficiency of close-coupled magnetic core versions.

What do they use to represent 'wireless' transmission?

https://www.allaboutcircuits.com/news/how-does-qi-wireless-charging-standard-work/
Transformers.