752 results about "Pseudo random sequence" patented technology

The objective of this invention is to provide continuous remote authenticated operations for ensuring proper content processing and management in remote untrusted computing environment. The method is based on using a program that was hidden within the content protection program at the remote untrusted computing environment, e.g., an end station. The hidden program can be updated dynamically and it includes an inseparable and interlocked functionality for generating a pseudo random sequence of security signals. Only the media server that sends the content knows how the pseudo-random sequence of security signals were generated; therefore, the media server is able to check the validity of the security signals, and thereby, verify the authenticity of the programs used to process content at the remote untrusted computing environment. If the verification operation fails, the media server will stop the transmission of content to the remote untrusted computing environment.

A technique is disclosed for establishing a secure communication link between a first computer and a second computer over a computer network. Initially, a secure communication mode of communication is enabled at a first computer without a user entering any cryptographic information for establishing the secure communication mode of communication. Then, a secure communication link is established between the first computer and a second computer over a computer network based on the enabled secure communication mode of communication. The secure communication link is a virtual private network communication link over the computer network in which one or more data values that vary according to a pseudo-random sequence are inserted into each data packet.

A technique is disclosed for establishing a secure communication link between a first computer and a second computer over a computer network. Initially, a secure communication mode of communication is enabled at a first computer without a user entering any cryptographic information for establishing the secure communication mode of communication. Then, a secure communication link is established between the first computer and a second computer over a computer network based on the enabled secure communication mode of communication. The secure communication link is a virtual private network communication link over the computer network in which one or more data values that vary according to a pseudo-random sequence are inserted into each data packet.

A digital video recorder (DVR) is disclosed comprising a unique ID, a hard disk drive (HDD) for storing a plurality of encrypted video programs and an encrypted file system, the encrypted file system comprising a plurality of encrypted file system entries for decrypting the plurality of video programs. The DVR further comprises host circuitry for interfacing with the HDD, the host circuitry comprising a cryptography facility for encrypting plaintext file system entries into the encrypted file system entries stored on the HDD, and for decrypting the encrypted file system entries read from the HDD into plaintext file system entries. The cryptography facility comprises a pseudo-random sequence generator, responsive to the unique ID, for generating a pseudo-random sequence. The cryptography facility further comprises an encoder for combining the pseudo-random sequence with the plaintext file system entries to generate the encrypted file system entries stored on the HDD, and a decoder for combining the pseudo-random sequence with the encrypted file system entries read from the HDD to generate the plaintext file system entries.

An encryption system comprises a pseudo-random number generator (KS) for generating a long pseudo-random sequence (S) from a shorter encryption key (K) and, if necessary, a nonce value (N), and a mixing function (MX) for combining the sequence with a plaintext message (P) on a block-by-block basis, where successive blocks (S(i)) of 128 bits of the sequence are combined with successive 64-bit blocks of plaintext (P(i)) to produce successive 64-bit blocks of ciphertext. The blockwise use of a long pseudo-random sequence preserves the advantages of a block cipher in terms of data confidentiality and data integrity, as well as benefiting from the speed advantages of a stream cipher.

A method for transmitting control information to a wireless node includes determining, by a communications controller, a first resource assignment parameter according to a pseudo-random sequence derived from an identifier, and mapping, by the communications controller, using the first resource assignment parameter, a demodulation reference signal associated with the wireless node onto a first resource located in a data region of a subframe. The method also includes mapping, by the communications controller, modulated control information associated with the wireless node onto a second resource located in the data region of the subframe, and transmitting, by the communications controller, the subframe to the wireless node.

Disclosed is an improved start-up / reset calibration apparatus and method for use in an SLDRAM memory device A 2N bit calibration pattern which is based on a pseudo random sequence is used to calibrate the relative timing of data and a latching clock signal to ensure optimal operation of the memory device. In addition, during calibration of one data path, other nearby data paths may receive in phase, out of phase and / or both in phase and out of phase versions of the calibration pattern so that the data path under calibration is calibrated under conditions which more closely approximate random operating conditions.

A method of estimating timing of at least one of the beginning and the end of a transmitted signal segment in the presence of time delay in a signal transmission channel. Each of a sequence of signal frames is provided with a pseudo-noise (PN) m-sequences, where the PN sequences satisfy selected orthogonality and closures relations. A convolution signal is formed between a received signal and the sequence of PN segments and is subtracted from the received signal to identify the beginning and / or end of a PN segment within the received signal. PN sequences are used for timing recovery, for carrier frequency recovery, for estimation of transmission channel characteristics, for synchronization of received signal frames, and as a replacement for guard intervals in an OFDM context.

A method of operating a wireless communication system is disclosed (FIG. 6). The method includes receiving a virtual cell identification (VCID) parameter (600) from a remote transmitter. A base sequence index (BSI) and a cyclic shift hopping (CSH) parameter (604,606) are determined in response to the VCID. A pseudo-random sequence is selected in response to the BSI and CSH (610,612). A reference signal is generated using the selected pseudo-random sequence (614).

A wireless local area network (WLAN) transmitter includes a baseband processing module and a plurality of radio frequency (RF) transmitters. The baseband processing module operably coupled to scramble data in accordance with a pseudo random sequence to produce scrambled data. The baseband processing module is further operably coupled to interleave, at a word level, the scrambled data to produce interleaved data when the interleaving is enabled. The baseband processing module is further operably coupled to outer Reed-Solomon encode the scrambled data or the interleaved data to produce outer encoded data when the outer Reed-Solomon encoding is enabled. The baseband processing module is further operably coupled to inner puncture convolution encode the outer encoded data or the scrambled data to produce the encoded data. The baseband processing module is further operably coupled to determine a number of transmit streams based on a mode selection signal. The baseband processing module is further operably coupled to convert the encoded data into streams of symbols in accordance with the number of transmit streams and the mode selection signal. The plurality of radio frequency (RF) transmitters, when enabled, converts the streams of symbols into a corresponding number of RF signals.

A method and apparatus of transmitting a reference signal in a wireless communication system is provided. A reference signal sequence is generated by using a pseudo-random sequence. A portion or entirety of the reference signal sequence is mapped to at least one resource block and is transmitted. The pseudo-random sequence is generated by a gold sequence generator which is initialized with initial values obtained by using cell identifier. The reference signal provides low PAPR and high cross correlation characteristic.

A method of operating a wireless communication system (FIG. 4) is disclosed. The method includes receiving downlink control information (702) for transmission to a user equipment (UE) in enhanced physical downlink control channel (EPDCCH). A pseudo-random number generator is initialized (706) for generating a pseudo-random sequence. A plurality of demodulation reference signals (DMRS) are generated with the pseudo-random sequence. The plurality of DMRS is mapped with the EPDCCH and transmitted to the UE (712).

A high speed, two-way serial interface with a scrambler and de-scrambler may be tested by sending a single word repeatedly through the scrambler to create a pseudo-random sequence. The pseudo-random sequence is then passed through the transmitter and looped back through the receiver of the serial interface. The pseudo-random sequence is then descrambled and compared to the input word. Since the input sequence is only a single word rather than a series of words, the comparison is very simple and capable of being performed within the serial interface itself without the need for external test equipment.

A frequency interleaving circuit frequency-interleaves main signals generated according to sound data by parameters set according to frequencies of transmission channels. A sub-signal generating circuit generates sub-signals for transmission control including pilot signals. Mapping circuits modulate the sub-signals by using pseudo-random sequences generated based on initial values of random codes set according to frequencies of transmission channels. The frequency-interleaved main signals and the sub-signals modulated by the mapping circuits are OFDM-modulated. Then, they are converted to the frequencies of the transmission channels. An increase of a dynamic range of transmission signals can be suppressed by controlling the initial values of random codes set.

A method is provided for extending a sequence repetition period of a random number generator in systems based on the availability of random sequences. The method includes performing RNS arithmetic operations to express a random number in a sequence as RNS residue values. Each generated random number has a value between zero and n!−1. The method also includes converting each of the RNS residue values to a relatively prime base number system so that each of the RNS residue values includes at least one digit. The method further includes generating an arbitrary permutation ordering of output sequence numbers using a select combination of digits associated with each of the RNS residue values. The arbitrary permutation ordering is applied to a cyclic structure having n elements. Each of the n elements has an associated output sequence number.

A method of securely deleting data from a storage medium includes generating a bitmap that corresponds to unused locations on the storage medium; initiating a background process that wipes the unused locations, where the background process runs asynchronously with a user application; wiping the unused locations; and updating the bitmap to reflect that the unused locations have been wiped. The wiping replaces data at the unused locations with random sequences, with pseudo-random sequences, with data generated by a secure deletion algorithm, with application data from the user application, or with all zeros. The wiping includes repeated writing of predetermined sequences to the unused locations. The wiping replaces data at unused locations that represent portions of any of blocks, clusters and sectors, and can wipe any metadata associated with files previously stored at any of the unused locations. Upon a request for access of data from a wiped location, data that does not correspond to data originally stored at the wiped location can be returned.

Data are embedded in an audio signal for watermarking, steganography, or other purposes. The audio signal is divided into time frames. In each time frame, the relative phases of one or more frequency bands are shifted to represent the data to be embedded. In one embodiment, two frequency bands are selected according to a pseudo-random sequence, and their relative phase is shifted. In another embodiment, the phases of one or more overtones relative to the fundamental tone are quantized.

A method for analyzing analytes from a sample introduced into a Spectrometer by generating a pseudo random sequence of a modulation bins, organizing each modulation bin as a series of submodulation bins, thereby forming an extended pseudo random sequence of submodulation bins, releasing the analytes in a series of analyte packets into a Spectrometer, thereby generating an unknown original ion signal vector, detecting the analytes at a detector, and characterizing the sample using the plurality of analyte signal subvectors. The method is advantageously applied to an Ion Mobility Spectrometer, and an Ion Mobility Spectrometer interfaced with a Time of Flight Mass Spectrometer.

The present invention discloses battery assisted RFID system RF power leveling methods that optimize the amount of transmitted power and interference from a reader in relation to the sensitivity of the RFID tags, their ranges from the reader, and the unique physics of the backscatter RFID radio link. These methods enhance system reliability when employing battery assisted RFID tags that operate with sensitive transistor based square law tag receivers and highly sensitive RFID readers intended to take advantage of outstanding tag sensitivity. Further enhancement is achieved via design of system command sets and tag state machine behavior that optimally support the power level operations, power level operations that span across tag hibernation and normal modes, and that otherwise control system interference. Embodiments of the present invention are also enhanced with receiver training and synchronizing methods suited to the high tag sensitivity and need for dynamic range state switching. These enhancements may employ pseudo-random sequence based receiver training, activation signaling, and frame synchronizing.

The invention relates to an electric prospecting method. In the method, a transmitter transmits a signal and a receiver processes the received signal to obtain impulse response and frequency response. The electric prospecting method is characterized by comprising the following steps of: transmitting a pseudo random sequence by using the transmitter; carrying out correlation operation on a time sequence received by the receiver by using the pseudo random sequence so as to obtain time domain impulse response; converting the time domain impulse response to frequency domain so as to obtain frequency response; and carrying out fitting and inversion by using a double Cole-Cole model so as to obtain parameters of a complex resistivity method.

A mass spectrometer and associated methods analyze an ion beam by accumulating ions for a sequence of time periods, and driving the accumulated ions in pulses. Differing quantities of ions can be accumulated in the sequential pulses according to a pseudo-random sequence, and the slower ions are overtaken by the faster ions of a subsequent pulse. A mass spectrum may be reconstructed from an overlapping ion detector signal using an inverse of a weighted simplex matrix or inverse Hadamard transform techniques.

An elevator car position measuring system includes a strip having a code mark pattern mounted near the elevator car and parallel to a travel direction, a code reading device mounted on the elevator car for contactless scanning of the code mark pattern and an evaluating unit connected to the code reading device for evaluating the scanned code mark pattern. A code word is formed by “n” successive code marks of the code mark pattern, a plurality of different ones of the code words are unambiguously arranged in an n-digit pseudo random sequence, the code words form a single-track of the code mark pattern and each of the code words represents an absolute car position. A floor sensor mounted on the elevator car detects position markings at floor levels along the travel direction and is connected to the evaluating units for evaluating the detected position markings against said scanned code words.

The present invention relates to a wireless communication system and a wake up method thereof. The wake up method includes the following steps: when main equipment has a communication requirement, the main equipment converts a pseudo random sequence code into a wake up bit stream through coding transformation, modulates the wake up bit stream into a wireless modulation signal, and sends the wireless modulation signal to at least one slave equipment in a preset duration time, wherein the preset time is greater than or equal to a sum of a dormancy period and a detection period of the slave equipment; each slave equipment receives the wireless modulation signal in the detection period, demodulates the wireless modulation signal into the wake up bit stream, carries out sampling and decoding on the wake up bit stream, and determines whether to wake up the slave equipment or not according to a decoding result. Through the implementation of a technical scheme of the invention, time synchronization of a wireless communication device involving communication does not needed; anti-interference ability is strong, problems of identity identification and false wake up are solved, and reliability is raised; the detection period of the salve equipment can be shortened, a receiving window time of the salve equipment is reduced, and power consumption of a communication system is reduced.

This invention relates to a dynamic random disturbance and cipher-decipher method of the video information characterizing in extracting several key data blocks for disturbance from the video information needing to be ciphered then to recover the disturbed data blocks to the extract position to be mixed with those nonkey data as the ciphered video stream to be output. The de-cipher process is similar to that. The matrix used in disturbance is dynamically generated by pseudo-random sequence, the disturbance matrixes are different to all video frames, security reaches the applied level. This invention can realize standard compressive video information cipher and decipher with hierarchy security.

The invention discloses a training sequence frame timing synchronized method based on pseudo-random sequence modulation, which can be applied in an orthogonal frequency division multiplexing system or a single carrier frequency domain equalization system, and comprises the following steps: (1) carrying out an energy detection by using the relevance of the front part and the back part of a training sequence at a receiving terminal; (2) taking the certain range around the peak position of the energy detection as a rough synchronization timing range; (3) in the rough synchronization timing range, using a local frame leading sequence generated by the receiving terminal to carry out the cross-correlation with a receiving sequence, according to the peak position of the cross-correlation, determining the position of the local frame accurate synchronization timing, wherein the first half part of the leading training sequence is gained by modulation of cascade sequence of self-correlation of a plurality of constant amplitude zero values by adopting the pseudo-random modulation sequence, and the second half part thereof is inverse operation of the first half part. The method can gain higher timing accuracy by using the pseudo-random modulation sequence to carry out the complex fine synchronization.

Embodiments of the present invention provide for RFID systems that employ a plurality of battery assisted semi-passive and semi-active RFID tags with optimized system operation. The RFID tags feature receivers operating with multiple dynamic range states with square law mode for improved sensitivity, and part time active transmit in the tag to supplement its backscatter transmitter and thus support system operation taking full advantage of the sensitivity of the tag. In certain embodiments of the invention, tag sensitivity and reliability are further enhanced by the use pseudo-random sequence based receiver training and frame synchronizing.

A method and apparatus of transmitting a reference signal in a wireless communication system is provided. A reference signal sequence is generated by using a pseudo-random sequence. A portion or the entirety of the reference signal sequence is mapped to at least one resource block, and is transmitted. The pseudo-random sequence is generated by a gold sequence generator which is initialized with initial values obtained by using cell identifier. The reference signal provides low PAPR and high cross correlation characteristic.

Semiconductor devices, a system including said semiconductor devices and methods thereof are provided. An example semiconductor device may receive data scheduled for transmission, scramble an order of bits within the received data, the scrambled order arranged in accordance with a given pseudo-random sequence. The received data may be balanced such that a difference between a first number of the bits within the received data equal to a first logic level and a second number of bits within the received data equal to a second logic level is below a threshold. The balanced and scrambled received data may then be transmitted. The example semiconductor device may perform the scrambling and balancing operations in any order. Likewise, on a receiving end, another semiconductor device may decode the original data by unscrambling and unbalancing the transmitted data. The unscrambling and unbalancing operations may be performed in an order based upon the order in which the transmitted data is scrambled and balanced.