I have a problem with a certain task.
The frequency of the signal sampling at the OFDM modulator output is 20 MHz. The length of the protection period is 2 microseconds and it is 20% of the whole symbol, including the cyclic prefix. The size of the transmitted data is 6 MB. The 16-QAM constellation is used in the subchannels.
My questions are
- how to calculate the data transmission time,
- how many bits are transmitted in one OFDM symbol,
- what is the FFT size,
- what is the bandwidth of the transmitted signal and
- what will be the effective transmission speed if 25% of subchannels will be used for transmitting pilots.
Each data stream is divided into groups of "n" bits. Then for example QPSK constellation will have 2 bits at a time, 64-QAM constellation: 6 bits at a time and 16QAM: 4 bits at a time. And we are using 16-QAM constellation, so the answer to the second question will be 4 bits, right?