Disclosed is a compensation circuit which includes a data analyzer that receives a first bit stream including first to N-th bits, counts a number of times of coincidence of each of first to 2.sup.M-th patterns each having an M-bit size from the first bit stream, and generates a first pattern stream including first to 2.sup.M-th count values each corresponding to the number of times of coincidence of each of the first to 2.sup.M-th patterns, and a compensation calculator that determines first to 2.sup.M-th compensation values based on the first pattern stream such that results of multiplying the first to 2.sup.M-th count values and the first to 2.sup.M-th compensation values one-to-one are even. “N” is a natural number, and “M” is a natural number smaller than “N”.

The telemetry system used in the measurement while drilling (MWD) or logging while drilling (LWD) is essentially a digital communication system. The fact of the special and hostile drilling environment limits the use of many advanced techniques and equipment, and thus results in a low data transmission rate. While increasing the data rate for the MWD/LWD telemetry system becomes a primary focus, maintaining the system reliability and the decoding quality at a high data rate is equally challenging. This invention presents digital signal processing solutions to a high performance telemetry system with the high data rate, high system reliability, and high decoding quality.

Disclosed is a compensation circuit which includes a data analyzer that receives a first bit stream including first to N-th bits, counts a number of times of coincidence of each of first to 2.sup.M-th patterns each having an M-bit size from the first bit stream, and generates a first pattern stream including first to 2.sup.M-th count values each corresponding to the number of times of coincidence of each of the first to 2.sup.M-th patterns, and a compensation calculator that determines first to 2.sup.M-th compensation values based on the first pattern stream such that results of multiplying the first to 2.sup.M-th count values and the first to 2.sup.M-th compensation values one-to-one are even. N is a natural number, and M is a natural number smaller than N.

The present invention describes a method and system for simultaneous transmission of data to coherent and non-coherent receivers. The method at the transmitter includes retrieving a base ternary sequence having a pre-defined length, obtaining one or more ternary sequences corresponding to data to be transmitted and transmitting the obtained one or more ternary sequences by the transmitter. The method steps at the receiver includes receiving one or more ternary sequences corresponding to the data transmitted, demodulating each of the received ternary sequences by correlating with all cyclic shifts of the base ternary sequence by the receiver if the receiver is a coherent receiver, demodulating each of the received ternary sequences by correlating with all cyclic shifts of the absolute of the base ternary sequence by the receiver if the receiver is a non-coherent receiver and detecting the transmitted data based on the cyclic shifts corresponding to maximum correlation values.

A method and a transmitter for transmitting a pay load sequence are provided. The transmitter includes a ternary sequence mapper configured to map a binary data sequence to a ternary sequence stored in the transmitter, and a pulse shaping filter configured to generate a first signal based on the mapped ternary sequence. The ternary sequence includes elements of 1, 0, and 1.

Systems and methods are disclosed for detecting sequences of symbols in a received signal in the presence of inter-symbol interference. Maximum Likelihood Sequence Detection (MLSD) is a known method for optimum detection of such sequences. To reduce the complexity of the MLSD, a Reduced-State Sequence Detection (RSSD) technique has been considered based on partitioning the states of the MLSD. In this approach, a simplified sequence detector is placed within a global decision feedback loop. The disclosed architecture shortens the feedback loop by moving the sequence detector outside the loop and converting the interaction between the two to a feed-forward manner. This is achieved through slicing the signal and closing a nested loop around the sliced bins. A further variant simplifies the detector even more by reducing the number of bins.

Systems and methods are disclosed for detecting sequences of symbols in a received signal in the presence of inter-symbol interference. Maximum Likelihood Sequence Detection (MLSD) is a known method for optimum detection of such sequences. To reduce the complexity of the MLSD, a Reduced-State Sequence Detection (RSSD) technique has been considered based on partitioning the states of the MLSD. In this approach, a simplified sequence detector is placed within a global decision feedback loop. The disclosed architecture shortens the feedback loop by moving the sequence detector outside the loop and converting the interaction between the two to a feed-forward manner. This is achieved through slicing the signal and closing a nested loop around the sliced bins. A further variant simplifies the detector even more by reducing the number of bins.

The present invention describes a method and system for simultaneous transmission of data to coherent and non-coherent receivers. The method at the transmitter includes retrieving a base ternary sequence having a pre-defined length, obtaining one or more ternary sequences corresponding to data to be transmitted and transmitting the obtained one or more ternary sequences by the transmitter. The method steps at the receiver includes receiving one or more ternary sequences corresponding to the data transmitted, demodulating each of the received ternary sequences by correlating with all cyclic shifts of the base ternary sequence by the receiver if the receiver is a coherent receiver, demodulating each of the received ternary sequences by correlating with all cyclic shifts of the absolute of the base ternary sequence by the receiver if the receiver is a non-coherent receiver and detecting the transmitted data based on the cyclic shifts corresponding to maximum correlation values.

The application relates to a receiving device for a communication system, where the receiving device includes a receiver configured to receive a Multiple-Input and Multiple-Output (MIMO) communication signal including a plurality of transmit symbols belonging to at least one complex-valued symbol constellation, a processing circuit configured to affine-transform the at least one complex-valued symbol constellation to obtain at least one affine-transformed complex-valued symbol constellation, compute a decision metric; based on the at least one affine-transformed complex-valued symbol constellation, detect the transmit symbols based on the computed decision metric.

The present invention describes a method and system for simultaneous transmission of data to coherent and non-coherent receivers. The method at the transmitter includes retrieving a base ternary sequence having a pre-defined length, obtaining one or more ternary sequences corresponding to data to be transmitted and transmitting the obtained one or more ternary sequences by the transmitter. The method steps at the receiver includes receiving one or more ternary sequences corresponding to the data transmitted, demodulating each of the received ternary sequences by correlating with all cyclic shifts of the base ternary sequence by the receiver if the receiver is a coherent receiver, demodulating each of the received ternary sequences by correlating with all cyclic shifts of the absolute of the base ternary sequence by the receiver if the receiver is a non-coherent receiver and detecting the transmitted data based on the cyclic shifts corresponding to maximum correlation values.