摘要:
A apparatus and method for estimating a sequence of transmitted quadrature amplitude modulation (QAM)-modulated signals and space-time block coded signals using an optimal expectation-maximization (EM)-based iterative estimation algorithm in a multiple-input and multiple-output (MIMO)-orthogonal frequency division multiplexing (OFDM) mobile communication system. An initial sequence estimation value is produced on the basis of a predetermined initial value using a pilot sub-carrier contained in each of OFDM signals received by a receiving side. A normalized value of a received signal on a channel-by-channel basis is produced by a predetermined equation using orthogonality between the OFDM signals received by the receiving side. At least one subsequent sequence estimation value is produced using the initial sequence estimation value and the normalized value of the received signal on the channel-by-channel basis. If the subsequent sequence estimation value converges to a constant value after an operation of producing the subsequent sequence estimation value is iterated the predetermined number of times, the converged subsequent sequence estimation value is designated as a final sequence estimation value.
摘要:
The present disclosure provides an apparatus and a method for preventing an Intermediate Frequency (IF) connector from being corroded in a portable terminal. The apparatus may comprise an IF connector and a load switch that is mounted in a main board. The load switch is configured to communicate with the IF connector and to prevent a reverse voltage from being applied to the IF connector.
摘要:
A data error correction circuit includes a plurality of one-bit registers, a data error detection unit and a data error correction unit. The data error detection unit detects whether all the data values stored in the plurality of the registers are equal. The data correction unit determines a correct data value based upon each of the stored data values, and corrects each of the data values into the determined correct data value if the data values are not equal. Therefore, the data error correction circuit may correct a data error due to electrostatic discharge (ESD) or electromagnetic interference (EMI).
摘要:
A data error correction circuit includes a plurality of one-bit registers, a data error detection unit and a data error correction unit. The data error detection unit detects whether all the data values stored in the plurality of the registers are equal. The data correction unit determines a correct data value based upon each of the stored data values, and corrects each of the data values into the determined correct data value if the data values are not equal. Therefore, the data error correction circuit may correct a data error due to electrostatic discharge (ESD) or electromagnetic interference (EMI).
摘要:
An automatic clustering method using an Average-linkage algorithm and a KPower Means algorithm, and a method and apparatus for multi-path clustering required for a spatial channel modeling (SCM) in a wireless communication environment are provided. The automatic clustering method, including: a first step of obtaining an initial cluster centroid using a hierarchical clustering algorithm; a second step of moving the initial cluster centroid using a two dimensional clustering algorithm; a third step of clustering a data set according to the moved initial cluster centroid; and a fourth step of calculating a validation index with respect to the clustered data set and determining an optimal number of clusters.
摘要:
A diaphragm pump having a simple structure for effectively preventing pulsation of liquid being discharged, which includes an air chamber connected to a head-side discharge hole of the diaphragm pump and having a discharge-side discharge hole, and thereby pipes are kept from being damaged by preventing the pulsation of the liquid, and the level of noisy can be reduced to a very adequate level.