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    I/Q baseband Modulator Demodulator

    hi,

    I want to understand I/Q modulation and demodulation process. I want to module a 10MHz bit stream (each bit has 100 nsec duration). Bit stream is in the form of 0 and 1. I want to perform BPSK.

    How can i convert it to i/q base-band? What is the significance of I/Q modulation and demodulation?

    Regards

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    Re: I/Q baseband Modulator Demodulator

    BPSK doesn't involve quadrature modulation, see https://en.wikipedia.org/wiki/Phase-shift_keying


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  3. #3
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    Re: I/Q baseband Modulator Demodulator

    Quote Originally Posted by adnan012 View Post
    hi,

    I want to understand I/Q modulation and demodulation process. I want to module a 10MHz bit stream (each bit has 100 nsec duration). Bit stream is in the form of 0 and 1. I want to perform BPSK.

    How can i convert it to i/q base-band? What is the significance of I/Q modulation and demodulation?

    Regards
    this technique is quite popularly used in bandpass modulation in Digital communication, you need to take a look at "Digital Communication book" (maybe chapter 4) from Prof. SKLAR first, then go further to mod/demo circuit later


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    Re: I/Q baseband Modulator Demodulator

    Quote Originally Posted by FvM View Post
    BPSK doesn't involve quadrature modulation, see https://en.wikipedia.org/wiki/Phase-shift_keying
    In this case I/Q-modulation is overkill, but I think it can be used to create any modulation.
    BPSK is easy to do, just set Q=0 and change I between +1 and -1 according to the data bits.
    A more complex example is SSB, which is possible but not trivial to do with I/Q-modulation. The modulation signal must be transformed.


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