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hello everyone,

i want to transmit random source signal to QAM modulation but there is no block in GNU radio, so can anyone help how can i use QAM modulation scheme in GNU radio?

i am using GNU radio version 3.10.

Thanks.

To implement QAM (Quadrature Amplitude Modulation) in GNU Radio, you can use a combination of existing blocks to create your QAM modulation scheme. Here's a step-by-step guide: heardle
1. Signal Source:
- Use the `Random` block to generate random data.
- Connect the `Random` block to a `Vector Source` block to convert the random data into a vector.
2. QAM Modulation:
- Use the `Constellation Modulator` block.
- In the Constellation Modulator block, set the modulation scheme to QAM and configure the constellation points.
3. Up-sampling:
- To ensure that the data rate matches your desired sample rate, use the `Repeat` block or `Interpolation` block to up-sample the signal.
4. Filtering:
- Apply a low-pass filter using the `Low Pass Filter` block to limit the bandwidth of the signal.
5. Signal Sink:
- Use a `File Sink` block to save the modulated signal to a file or a `QT GUI Sink` block to visualize the signal.

You can use the gnuradio.digital.qam_mod block, which is a hierarchical block for RRC-filtered QAM modulation. The input to this block is a byte stream (unsigned char), and the output is the complex modulated signal at basebandhttps://www.gnuradio.org/doc/sphinx-v3.7.10.0/digital.html

It makes me so happy to have found this helpful website. It teaches me a lot of interesting things shell shockers

mitesh wrote: ↑Fri Nov 24, 2023 11:14 pm hello everyone,

i want to transmit random source signal to QAM modulation but there is no block in GNU radio, so can anyone help how can i use QAM modulation scheme in GNU radio?

i am using GNU radio version 3.10.papa's games

Thanks.

QAM is widely used as a modulation technique in digital communications systems, including 802.11 Wi-Fi standards.