Abstract: A system, apparatus and method for a multi-stage Parallel Residue Compensation (PRC) receiver for enhanced suppression of the Multiple Access Interference (MAI) in Code Division Multiple Access (CDMA) systems. The accuracy of the interference estimation is improved with a set of weights computed from an adaptive Normalized Least Mean Square (NLMS) algorithm. In order to reduce complexity, the commonality of the multi-code processing is extracted and used to derive a structure of PRC to avoid direct interference cancellation. The derived PRC structure reduces the interference cancellation architecture from a complexity that is proportional to the square of the number of users to a complexity that is linear with respect to the number of users. The complexity is further reduced by replacing dedicated multiplier circuits with simple combinational logic.

Abstract: An apparatus and corresponding method for receiving a MIMO cellular communication signal, the apparatus including: a Kalman filter type of equalizer, responsive to a received signal, for providing a corresponding processed signal indicating information conveyed by the received signal, responsive to a set of values indicating predicted state error correlation at a first instant of time given all noise estimates up through the first instant, for providing ta set of values indicating a product of measurement values and predicted state error correlation at a later instant of time given all process noise estimates up through the later instant. The filter is implemented so as to make use of the displacement structure of the state transition matrix of the Kalman filter allowing shifting operations in place of vector and matrix multiplications.

Abstract: Disclosed is a LMMSE receiver that restores orthogonality of spreading codes in the downlink channel for a spread spectrum signal received over N receive antennas. The FFT-based chip equalizer tap solver reduces the direct matrix inverse of the prior art to the inverse of some submatrices of size N×N with the dimension of the receive antennas, and most efficiently reduces matrix inverses to no larger than 2×2. Complexity is further reduced over a conventional Fast Fourier Transform approach by Hermitian optimization to the inverse of submatrices and tree pruning. For a receiver with N=4 or N=2 with double oversampling, the resulting 4×4 matrices are partitioned into 2×2 block sub-matrices, inverted, and rebuilt into a 4×4 matrix. Common computations are found and repeated computations are eliminated to improve efficiency. Generic design architecture is derived from the special design blocks to eliminate redundancies in complex operations. Optimally, the architecture is parallel and pipelined.

Abstract: A receiver, such as a CDMA MIMO receiver, includes a LMMSE-based chip-level equalizer constructed so as to implement a FFT accelerated iterative algorithm having a complexity of order O(Nlog2(N)), where N is the dimension of a covariance matrix. The equalizer uses one of an overlap-save or an over-lap add FFT architecture.

Abstract: A transportation device for transferring material from a higher elevation at an outdoor location to a lower elevation at an indoor location, such as a basement, via a chute assembly, specifically an exterior chute loaded wood transportation and storage device. The chute may be of varying lengths depending on the distance to be traveled. The chute may remain in position or be removed when not in use with corresponding closure means to prevent precipitation, animals, or outdoor air from entering the house. A wood storage bin, with holes to facilitate air flow, may be placed near the foot of the chute in the indoor location to receive and store the wood.

Abstract: A chute assembly for connecting an elevated area to a lower area, such as within a cellar entry enclosure, for transporting items. The chute assembly may also include a bin enclosure for storage of the items in addition to transporting them.

Abstract: A gravimetric cell for centrifugal separation of fine coal by density has a cylindrical body and a butterfly valve or other apparatus for selectively sealing the body radially across the approximate center of the cylinder. A removable top is provided which seals the cylinder in the centrifuge and in unvented areas.