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# developing a theoretical model , looking for answeres

## developing a theoretical model , looking for answeres

(OP)
Hello to everyone following this thread . Im try to develope a theoretical model . Im looking for answeres in several disciplines . Re ; electrical theory and radio theory  my questions are  ,

Waves can be broken into two types , Linear - sine waves and Non Linear standing or stationary waves    ??

Sine waves can be detected and measured over time as a function of frequency    ?

Standing - stationary waves can be detected and measured over space , and as such can be called a function of space ?

Re; general radio theory .  As frequency increases propagation over space decreases  ??

If true , As frequency decreases propagation over space increases   ?

Re ; radio theory . Is band width a function of
frequency  ?

If so , as frequency increases - band width increases ?

Likewise , As frequency decreases - band width decreases  ?

Re ; electrical theory & radio antennas

Operating at extremely low RF frequencies is it possible to create a virtual antenna if frequency of operation and voltage applied to a antenna are phase synchd
, In essence the field becomes the antenna    ???

Best regards          mangomike
Replies continue below

### RE: developing a theoretical model , looking for answeres

Hello, I will take a crack at answering your questions.  They are not quite clear as to what you want to know, but here goes.
Standing waves are a function of impedance, not space.  They are what happens when the load at the end of the transmission line is a different impedance from the transmission line.
Propagation - path loss in space is constant.  In the atmosphere, it is a function of frequency.
Bandwidth - it is a function of the modulation rate of the carrier.  You can have a 1 Hz wide carrier at any frequency as long as it is not modulated.  Adding modulation increase the bandwith used by the carrier.
Virtual antenna - I don't understand the question.

### RE: developing a theoretical model , looking for answeres

(OP)
Hello Lewish ,
Thanks for the response . Im sorry for the confusion I will rephrase my questions and give examples .
Digital radio recievers operate by detecting and measuring changes in ;  Frequency , Amplitude and / or Phase   - correct  ?

Generally speaking the RF signals / waves are linear as they travel through space   - correct  ?

Linear wave propagation characteristics typically decrease as frequency increases  .  Example ; satelite communications in the UHF - SHF +  is LOS (line of sight) and does not propagate  to the other side of the planet .
Like wise submarine signalling -communications will use VLF - ULF because of the penetration and increased range and propagation , Although sending a group of letters - numbers via telex takes time due to the low frequencies their operating on and reduced bandwidth . The same reason OTH ( over the horizon ) radar systems employ the use of the HF (high freq. ) band for detection and ranging because of the increased distances due to the band characteristics .

Another example of bandwidth increasing as higher and higher frequencies are used is ; fiber optics .

The statement Im trying my best to confirm is
" as frequency is increased in the E/M spectrum propagation over distance generally decreases "  .  ??

As for the non linear standing wave question Ill save that as a reply on this thread , Believe me Im not trying to pull teeth here just dialog .  One step at a time  : )

Thanks in advance for a response   .

Best regards     mangomike

### RE: developing a theoretical model , looking for answeres

OK, let's see....
Digital radio - all three are correct.

Submarine signalling - this uses a surface wave for propagation, not a space wave, and they use enormous amounts of power: try 2 times 10 to the 9th power watts.

Fiber optics - bandwidth is limited by inefficient optical filters.  Theoretically, you can still get a signal of 1Hz bandwidth down a fiber.

More later.

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