Abstract: The present invention discloses a channel estimation method and device in a multi-antenna system. The method includes: obtaining the original channel estimation value of each array element of an array antenna for each uplink user received by the antenna; converting them into a channel estimation matrix; dividing the channel estimation matrix into an amplitude matrix and a phase matrix; grouping the elements of each array element at the same tap location in the amplitude matrix together for signal transformation processing and performing transform domain noise reduction to the high-frequency portion of the obtained transform domain data; inversely transforming the noise-reduced data to a noise-reduced amplitude matrix; and combining the noise-reduced amplitude matrix with the phase matrix into a restored channel estimation matrix, wherein the amplitude of each channel estimation value of the restored channel estimation matrix has undertaken a multi-antenna transform domain noise reduction process.

Abstract: The present invention discloses a channel estimation method and device in a multi-antenna system. The method includes: obtaining the original channel estimation value of each array element of an array antenna for each uplink user received by the antenna; converting them into a channel estimation matrix; dividing the channel estimation matrix into an amplitude matrix and a phase matrix; grouping the elements of each array element at the same tap location in the amplitude matrix together for signal transformation processing and performing transform domain noise reduction to the high-frequency portion of the obtained transform domain data; inversely transforming the noise-reduced data to a noise-reduced amplitude matrix; and combining the noise-reduced amplitude matrix with the phase matrix into a restored channel estimation matrix, wherein the amplitude of each channel estimation value of the restored channel estimation matrix has undertaken a multi-antenna transform domain noise reduction process.

Abstract: What is disclosed is a system and method for efficiently and accurately estimating the complete TRC for a color marking device equipped with a multi-center cluster halftone screen which has a similar halftone tiling geometry and a similar growth specified by a corresponding single-center cluster halftone screen. The present method introduces a cluster-based printer model which establishes a relationship between a color output of a single-center cluster halftone screen and a color output of a multi-center cluster halftone screen. The present cluster-based printer model determines the complete TRC for the multi-center cluster halftone screen using the measurements for the single-center cluster halftone screen. Results of halftone dot linearization with different printing devices demonstrates that high accuracy can be achieved using the reduced measurements from the single-center cluster halftone screen.

Abstract: A bed sheet with elastic side panels is made of a material body configured to substantially cover a mattress. The sheet is provided with a foot and head elastic panels that cover and end region of the mattress and side panels. A portion of each side panel adjacent the mattress corner is made of an elastic material. The foot and head elastic panels extend to and connect to the elastic portions of the sides panels. The elastic panels can be configured of one sheet of material in common with the foot and head panels or as separate panels covering an end portion, and opposing side portions. These separate panels are joined at the apex of a corner of the mattress.

Abstract: A bed sheet is made of: a material body with inner and outer surfaces configured to substantially cover a mattress. The sheet is provided with at least one pair of co-located pockets provided on the material body. The pockets are substantially rectangular and are placed one on top of the other. The outermost pocket has a height less than that of the inner pockets. The top edges of each pocket are open and slope in opposite direction to facilitate selective placement of objects in one pocket or the other.

Abstract: A marking device is controlled to mark a media sheet with halftone dots selected from a set of image halftone dot representations. The marking device is controlled to mark a monitored surface with halftone dots selected from a set of control halftone dot representations to form test patches of different nominal marking densities. Measured marking densities are acquired using a density sensor for the test patches marked on the monitored surface. The set of control halftone dot representations is updated based on the measured marking densities and the nominal marking densities.

Abstract: What is disclosed is a system and method for efficiently and accurately estimating the complete TRC for a color marking device equipped with a multi-center cluster halftone screen which has a similar halftone tiling geometry and a similar growth specified by a corresponding single-center cluster halftone screen. The present method introduces a cluster-based printer model which establishes a relationship between a color output of a single-center cluster halftone screen and a color output of a multi-center cluster halftone screen. The present cluster-based printer model determines the complete TRC for the multi-center cluster halftone screen using the measurements for the single-center cluster halftone screen. Results of halftone dot linearization with different printing devices demonstrates that high accuracy can be achieved using the reduced measurements from the single-center cluster halftone screen.

Abstract: A marking device is controlled to mark a media sheet with halftone dots selected from a set of image halftone dot representations. The marking device is controlled to mark a monitored surface with halftone dots selected from a set of control halftone dot representations to form test patches of different nominal marking densities. Measured marking densities are acquired using a density sensor for the test patches marked on the monitored surface. The set of control halftone dot representations is updated based on the measured marking densities and the nominal marking densities.

Abstract: A non-destructive technique and related array for writing and reading magnetic memory cells, including sampling a first signal of a selected read line corresponding to select memory cells, applying a magnetic field to the select memory cells, sampling a second signal of the selected read line, and comparing the first and second signals to determine a logic state of the select memory cells.

Abstract: A method of controlling an actuator includes determining a function of an actuator value based on a cost function index that represents a relationship between a tone reproduction curve error and the actuator value necessary to achieve a tone reproduction curve target, determining an actual tone reproduction curve error from an obtained sample of a tone reproduction curve and controlling the actuator based on the function and actual tone reproduction curve error to move to a point that represents the tone reproduction curve target. A Xerographic system includes an actuator, an input device that inputs the cost function index and a controller that controls the Xerographic system to obtain the sample, determine an actual tone reproduction curve error from the sample, and control the actuator based on the cost function index and the actual tone reproduction curve error to move to a point that represents the tone reproduction curve target.

Abstract: A non-destructive technique and related array for writing and reading magnetic memory cells, including sampling a first signal of a selected read line corresponding to select memory cells, applying a magnetic field to the select memory cells, sampling a second signal of the selected read line, and comparing the first and second signals to determine a logic state of the select memory cells.

Abstract: A method of controlling an actuator includes determining a function of an actuator value based on a cost function index that represents a relationship between a tone reproduction curve error and the actuator value necessary to achieve a tone reproduction curve target, determining an actual tone reproduction curve error from an obtained sample of a tone reproduction curve and controlling the actuator based on the function and actual tone reproduction curve error to move to a point that represents the tone reproduction curve target. A Xerographic system includes an actuator, an input device that inputs the cost function index and a controller that controls the Xerographic system to obtain the sample, determine an actual tone reproduction curve error from the sample, and control the actuator based on the cost function index and the actual tone reproduction curve error to move to a point that represents the tone reproduction curve target.

Abstract: Systems and methods for measuring and setting grid voltages in an image forming device may include setting a first charging device of a first image forming station to a first voltage level and setting a second charging device of the first image forming station to be off; charging a charge-retentive surface with the first charging device set at the first voltage level; measuring and the charge imparted to the charge-retentive surface by the first charging device; storing the measured charge value. Systems and methods may further include repeating the setting, charging, measuring and storing steps for the first charging device for at least one additional voltage level; and determining at least one parameter of the first charging device based on the stored measured charge values for the first charging device for each voltage level.

Abstract: An in situ system and method for setting the charge voltages in a dual recharge color photocopier device includes a calculating an optimal DC grid voltage for each DC charging device of the dual recharge photocopier device. With the AC charging devices off, the photoreceptor belt is advanced to the first color station at a uniform residual voltage level. The DC charge device for the first color station charges the photoreceptor belt to a uniform voltage level. An non-contact voltmeter measures and stores the value read from the photoreceptor belt. An exposure device at the first color station exposes a portion of the photoreceptor belt to be read by the voltmeter at the next color station. The process continues through each color station, reading the voltage level of the portion of the photoreceptor belt exposed at the previous color station until voltage readings have been obtained for each color station.