1. bandwidth determines subcarrier frequency spectrum
2. the duration of the data is determined by grant time
3. all 1500 frequencies are required to represent a sequence of symbols
ie IFFT is
1500 x 1 mul 1 x 1500 matrix multiplication
64 QAM at a go can decode 1 symbol of 8bits or 1 byte, in the cartisian coordinates amplitude and angles representthe 64 points on the graphs each representing particular symbol
incoming bitstream is organized as a 8bits or 1 symbol, they are then imprinted on a frequency, converted to time domain, raised by central frequency and sent out
phy starts with broadcasting zadoff-chou preambles from common shared set, eNb uses a ra process to select the UE and assigns dedicated resource for future communication with the UE
so when contention is resolved or a dedicated zadoff-chou preamble is detected , phy becomes ready to forward the accompanying messages to FFT of eNb side
phy view
phy has two threads
one deals with RACH
other with other channels
when RACH thread is done ,it handovers to other thread
when other thread needs RACH it invokes that
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