Denoting o j as the j-th row in h k of length SF, we assign a multi-sequence (mathbf {S}_{i}^{text {SF}}), with i∈{0⋯N−1} as the ith multi-sequence of spreading factor SF. It is built as follows.
Due to the white noise-like pseudo-noise sequence of the spreading waveform, the AF of p t) has a property of superb time-frequency concentration, which means that the energy of p t) is concentrated in a very small time-frequency region −T c <τ
There are still missing components in our modeling; additions of other economic channels, such as the financial links which are thought to be a major origin of the current turmoil, would result in a better episode-specfic explanation of the sequence of crisis spreading dynamics.
DCI was detected in seven patients and was time-locked to a sequence of recurrent spreading depolarisations in all seven cases.
This ensures that each symbol is spread by a unique pre-coded spreading sequence, while making sure that the concatenated spreading sequence is orthogonal to the remaining set of spreading sequences at the transmitter.
The first discrete bit loading algorithm will use the mean system value λmean to determine the optimum number K∗ of spreading sequences and to select the sequences prior to allocating the energy for each sequence.
When does not coincide with any of the Doppler frequencies, the spreading function displays a random sequence of peaks spread over all possible delays.
Accordingly, as illustrated in Figure 3, the input data stream is demultiplexed into parallel streams,, with the individual data streams,, being spread by a number of spreading sequences, (multicode usage) and scrambling sequences (not depicted in Figure 3).
Based on a single Chu sequence, the proposed sophisticated FSOK scheme can generate a group of spreading sequences for the parallel substreams of multiple users, while maintaining low PAPR and orthogonality between substreams and users, even in the presence of multipath fading channels.
In such difficult situations, instead of considering complex scrambling code synchronization, we rather propose to build orthogonal families of codes made of spreading sequences with flat spectra inside the sequences bandwidth.
The design of spreading sequence is crucial to MUSA [11].
