This could be done like this. First make twenty oscillators, 100Khz apart above 5MHz. Modulte them individualy with your signal.Combine outputs of all frequency.Filter carrier and upper side band.You will get your 20 channels in 5-7MHz. Now modulate your uhf oscilator with this signal.The output will be above and below 5-7MHz of yor uhf carrier frequency. Filter upper side band for further amplification and output.You will get your 20 channels above 5-7MHz to your uhf carrier frequency.
This is same as fm and tv transmitters carry different audio and data channels on a single carrier. You have to choose frequencies to accomodate in legal bands.
Most people use a phase locked loop and a vco to do this. They do that because it is very frequency stable.
But if that is too expensive, a tunable resonator (something with a varactor diode) in the oscillator (instead of a crystal or saw resonator) will hop the frequency as a function of tuning voltage.
I think you gave yourself a difficult task.
I would still go for the synchronous data stream- you can asynchronously transform the "wild" data onto sync data.
I do not think the 432 MHz band offers enough bandwidth for your ten OOK data channels.
I think there are 432,434, etc, SAW resonators available for small keychain oscillators. I would suggest trying to pull their frequencies but any external reactance usually degrades their Q.
For multichannel oscillators, you could use a synthesizer with a fast frequency-switching response. A similar frequency source you would need at the receiver. Filtering the sidebands will be tricky and crosstalk between the channels rather poor.
As you never mentioned any parameters of your input data, it is difficult to think about details. I have already advised you to try designing a two-channel system with a variable carrier frequency, then you could test it and see if the crosstalk is acceptable, adjust filtering, etc. Only by experiments you could see if such system can work.
The RC airplane or car models utilize well designed multi-channel data transmission. Maybe you could try that way, and use two-three such systems (304 channels each) on separate carriers summed, then all upconverted e.g. to 432 MHz band. Depends on that if you need a working system, or, something to play with for a long time. I prefer simple things, and many have already been invented.
The signal characteristic questions from the previous thread essentially haven't been answered. https://www.edaboard.com/threads/226343/#post991463I have read but can not find any information why a synchronous system not can be used.
CC1101 and CC110L can be used for strictly asynchronous transmission by referring to an asynchronous serial option, that's provided for backward compatibility. The predecessor Chipcon/TI chips can anyway.Like I mention several times before I can't use these chips, becous they are for synchronous systems. Please read this topic more cearfully to understand my problem.
This picture looks nice, but it's quite theoretical. I need more explanation about practical implementation. For example how to generate 60, 61, 62 MHz.... Frequencies? Do I need 60 oscillators? Where I can get them? Any product code? Also suggest me please real commponent for first MIX? And what is Power Combiner? Can you give me please real product code for this purpuse? Also why I need 60-80MHz bandpass filter?
I have read but can not find any information why a synchronous system not can be used. Because it adds delay? You seems to accept different kinds of delays related to bandwidth and such.
I do not get your problem. You can set up 20 CC1101s and OOK each one of them asynchronously. They would each be phase locked to some central crystal, so they would not drift in frequency.
Why do you need 20 frequencies? Are there 20 parallel bits coming in, or just one bit stream?
i can send asynchronous data, but you do not seem open to suggestions, so good luck.
Excuse me, but that's what people call ignorance. Related to CC1101 properties, you're just guessing, isn't it?I will repeat again. I can't use microcontroller and CLK, but CC1101 must have them both. And if it has a clk it can't send asynchronous data.
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