Dr_Doggy
Well-Known Member
ok, so maybe i watch too much youtube, but this is just soo cool@!
and now i really need one!
I have been studying about how basic radar works, and it is very interesting how mixing works, where they combine the ghz high frequency, and from frequency mixing comes khz wave, which represents distance, very sleek and simple!
But then they get in to the phased array antenna which is also cool by using phase shift(delay) between two transmitters(or array) to propagate the beam in a unified direction, also going back , I remember they do similar for the directional speaker array in this example:
https://blog.takafumiide.com/2010/11/parametric-speaker/
But in order to steer the beam, they need to phase shift the signal going to output transmitters,
1)my question is what circuit can i use to do this(steer a beam)? the best i found were these:
**broken link removed**
https://en.wikipedia.org/wiki/Phase-shift_oscillator
is there something better/simpler, i think i would want a stage that works nice with a vco, could i use a pll chip?
2) for TX i would use the example where they use a ramp generator to run a vco, would above work for the situation of variable frequencies, and also what is the point of using this type of chirp in radar, and would pll still work?
3) what if i change the situation where i have fixed transmitter-across the room. and 2 receivers, would i just use the mixer method to compare the RX distances of echos ,?
4) Is the matrix in the Parametric speaker controlled like this, I imagine/read that there is phase delay between the center and edge peizo s , but could not identify which part of circuit is controlling this?
I have been studying about how basic radar works, and it is very interesting how mixing works, where they combine the ghz high frequency, and from frequency mixing comes khz wave, which represents distance, very sleek and simple!
But then they get in to the phased array antenna which is also cool by using phase shift(delay) between two transmitters(or array) to propagate the beam in a unified direction, also going back , I remember they do similar for the directional speaker array in this example:
https://blog.takafumiide.com/2010/11/parametric-speaker/
But in order to steer the beam, they need to phase shift the signal going to output transmitters,
1)my question is what circuit can i use to do this(steer a beam)? the best i found were these:
**broken link removed**
https://en.wikipedia.org/wiki/Phase-shift_oscillator
is there something better/simpler, i think i would want a stage that works nice with a vco, could i use a pll chip?
2) for TX i would use the example where they use a ramp generator to run a vco, would above work for the situation of variable frequencies, and also what is the point of using this type of chirp in radar, and would pll still work?
3) what if i change the situation where i have fixed transmitter-across the room. and 2 receivers, would i just use the mixer method to compare the RX distances of echos ,?
4) Is the matrix in the Parametric speaker controlled like this, I imagine/read that there is phase delay between the center and edge peizo s , but could not identify which part of circuit is controlling this?
