Abstract: Adjusting parameters of a waveform includes facilitating wireless communication between a transmitting node and receiving nodes, where the transmitting node communicates with a receiving node over a channel. Spectrum conditions are estimated, where a spectrum condition describes spectrum utilization in the vicinity of surrounding nodes. Channel conditions are estimated, where a channel condition describes a channel of the plurality of channels. Waveform parameters are adjusted in response to the spectrum conditions and the channel conditions.

Abstract: Communicating between a plurality of nodes includes: at one or more of the plurality of nodes, sensing spectrum activity on at least one channel; creating and maintaining at least one spectrum awareness table based at least in part on the sensed spectrum activity, determining at least one selected bearer based on the at least one spectrum awareness table; performing an adaptive control channel initialization operation to detect zero or more neighbor nodes.

Abstract: Establishing communications between a plurality of nodes includes determining a set of frequencies to search for neighbor nodes, and performing an adaptive control channel initialization operation to detect zero or more neighbor nodes. If one or neighbor nodes are detected, an adaptive control channel with one or more of the one or more detected neighbor nodes is established.

Abstract: Establishing communications between a plurality of nodes includes determining a set of frequencies to search for neighbor nodes, and performing an adaptive control channel initialization operation to detect zero or more neighbor nodes. If one or neighbor nodes are detected, an adaptive control channel with one or more of the one or more detected neighbor nodes is established.

Abstract: Adjusting parameters of a waveform includes facilitating wireless communication between a transmitting node and receiving nodes, where the transmitting node communicates with a receiving node over a channel. Spectrum conditions are estimated, where a spectrum condition describes spectrum utilization in the vicinity of surrounding nodes. Channel conditions are estimated, where a channel condition describes a channel of the plurality of channels. Waveform parameters are adjusted in response to the spectrum conditions and the channel conditions.

Abstract: Communicating between a plurality of nodes includes: at one or more of the plurality of nodes, sensing spectrum activity on at least one channel; creating and maintaining at least one spectrum awareness table based at least in part on the sensed spectrum activity, determining at least one selected bearer based on the at least one spectrum awareness table; performing an adaptive control channel initialization operation to detect zero or more neighbor nodes.

Abstract: Control circuitry for a disk drive system that has improved data detection by using log likelihood values and erasure pointers. The control circuitry is comprised of a log likelihood modification system and a decoder. The log likelihood modification system receives log likelihood values that represent data and erasure pointers. The erasure pointers point to at least one of the log likelihood values that has been corrupted in some manner. The log likelihood modification system sets the log likelihood values, that the erasure pointer points to, to an error value to generate modified log likelihood values. The log likelihood modification system transfers the modified log likelihood values to the decoder. The decoder processes the modified log likelihood values based on code constraints to generate estimated log likelihood values. The decoder then decodes the data from the estimated log likelihood values.

Abstract: Data storage system circuitry comprises randomizer circuitry and grading circuitry. The randomizer circuitry concurrently generates multiple randomized versions of user data. The grading circuitry selects one of the multiple randomized versions of the user data for data storage. Decoding circuitry decodes the selected one of the multiple randomized versions of the user data. In some examples of the invention, the grading circuitry selects the one of the multiple randomized versions of the user data based on zero run characteristics of the multiple randomized versions of the user data. In some examples of the invention, the user data is not encoded with a run length limit algorithm.

Abstract: In a sampled amplitude read channel for disk storage systems, a post processor is employed to correct errors in a preliminary sequence caused by the dominant error events of a trellis sequence detector. By correlating a sample error sequence with the dominant error events, error filters compute a Euclidean distance error metric between the samples sequence selected by the trellis sequence detector and the sample sequence that would have been selected if an error event did not occur. The minimum error metric is assigned to the symbols in the preliminary sequence that differ from the symbol sequence that would have been generated if the error event did not occur. After processing a predetermined number of the symbols in the preliminary sequence, the error metrics assigned, to the symbols are used to detect and correct error events in the preliminary sequence.

Abstract: Data storage system circuitry comprises randomizer circuitry and run-length control circuitry. The randomizer circuitry generates randomized user data. The run-length control circuitry grades the randomized user data to determine if the randomized user data requires run-length encoding. The run-length control circuitry applies the run-length encoding to the randomized user data if the randomized user data requires run-length encoding. The run-length control circuitry may encode decoding information and error correction information for the decoding information into the randomized user data. The run-length encoding may comprise de-randomization or RLL encoding. If de-randomization is used, RLL encoding may be eliminated altogether for the randomized user data.

Abstract: A sampled amplitude read channel is disclosed for disk storage systems comprising a encoder/decoder for implementing a high rate channel code that codes out specific minimum distance error events of a trellis sequence detector by enforcing a particular code constraint. The trellis sequence detector comprises a state machine matched to the code constraint which effectively removes the corresponding minimum distance errors from the detected output sequence. Additionally, the channel code encodes redundancy bits into the write data for implementing an error detection code. The redundancy bits are processed during a read operation to generate an error syndrome used to detect and correct other dominant error events, such as the NRZ (+) and (+−+) error events. In this manner, the most likely error events of the trellis sequence detector are either coded out by the channel code constraint, or detected and corrected using the error syndrome.