Abstract: An OFDM communication system performs time domain channel estimation responsive to received symbols before the symbols are processed by a fast Fourier transform. The communication system generates virtual pilots from actual pilots to improve the stability and quality of channel estimation. The system generates a reference signal from the actual and virtual pilots and correlates the resulting reference signal with a signal responsive to the received symbol to generate an initial channel impulse response (CIR) and to determine statistics about the channel. In some circumstances, the resulting reference signal is correlated with a modified symbol in which the actual and virtual pilot locations are emphasized and the data locations are deemphasized. Time domain channel estimation iteratively improves on the initial CIR. The system determines channel estimates for data only symbols through averaging such as interpolation.

Abstract: A roller track assembly for use with a product display includes a roller having opposing support portions. An inner casing includes a base and opposing side walls extending orthogonally from the base. One of the opposing side walls forms a notch configured to receive one of the opposing support portions of the roller and defining a first interior surface. An outer casing has first and second walls in a parallel relationship with the opposing side walls of the inner casing. The first wall of the outer casing forms a notch configured to receive the one of the opposing support portions of the roller and defining a second interior surface. The outer casing is positioned with respect to the inner casing such that the one of the opposing support portions is cooperatively retained in place by a portion of the first interior surface and a portion of the second interior surface.

Abstract: An OFDM receiver receives OFDM symbols in the frequency domain and comb filters and then punctures the OFDM symbols to leave symbols with actual pilot information and with null values at the data symbols. The receiver provides the punctured OFDM symbols to an OFDM symbol queue. A virtual pilot interpolator is coupled to the punctured OFDM symbol storage to generate virtual pilot information introduced to OFDM symbols. The interpolator may be a two dimensional Wiener filter. The receiver also includes a time domain channel estimator that processes a first OFDM symbol including virtual pilot information to generate a channel impulse response for the first OFDM symbol. A frequency equalizer equalizes the OFDM symbol in response to the channel impulse response for the first OFDM symbol.

Abstract: An OFDM receiver generates an initial channel impulse response in response to a received OFDM signal. The receiver determines the time span within the initial channel impulse response in which significant paths are present. An intermediate channel impulse response estimator identifies paths within the initial channel impulse response and generates an improved intermediate channel impulse response. A channel impulse response estimator performs a second non-linear process to generate a channel impulse response. An equalizer responds to the channel impulse response and the OFDM symbol to equalize the OFDM symbol. Metrics are generated that can be used for effectively stopping the second iterative non-linear process.

Abstract: A shelving system includes a retaining wall having a panel of integrally formed flanges extending therefrom in spaced columns and rows, with each flange defining a pocket with the panel. The system includes one or more shelves, with each shelf including a support platform, opposing side panels, and a back panel extending from the support platform. A portion of the back panel forms a hook configured for engagement with one of the pockets.

Abstract: An OFDM communication system performs time domain channel estimation responsive to received symbols before the symbols are processed by a fast Fourier transform. The communication system generates virtual pilots from actual pilots to improve the stability and quality of channel estimation. The system generates a reference signal from the actual and virtual pilots and correlates the resulting reference signal with a signal responsive to the received symbol to generate an initial channel impulse response (CIR) and to determine statistics about the channel. In some circumstances, the resulting reference signal is correlated with a modified symbol in which the actual and virtual pilot locations are emphasized and the data locations are deemphasized. Time domain channel estimation iteratively improves on the initial CIR. The system determines channel estimates for data only symbols through averaging such as interpolation.

Abstract: A modular shelving system comprises a first upright, a second upright, first and second rails, and a rail spanner. The first upright includes a first body and a first cleat having a base portion secured in the first body. The second upright includes a second body and a second cleat having a base portion secured in the second body. Each of the first and second rails defines an upper cleat hole and a lower cleat hole. The first cleat of the first upright is slidably received in the upper and lower cleat holes of the first rail, and the second cleat of the second upright is slidably received in the upper and lower cleat holes of the second rail. The rail spanner extends between the first and second rails and includes first and second retaining claws each connected to the rail spanner.

Abstract: A software upgrade application can be downloaded to a handset to selectively enable enhanced functionality physical layer circuitry. In a particular implementation, an OFDM handset or other portable modem includes selectively enabled time domain channel estimation circuitry. An upgrade application within the handset is activated. The handset is checked to confirm compatibility with the enhanced functionality and the upgrade application is checked to confirm its authenticity. The upgrade application then activates the enhanced functionality within the physical layer of the device.

Abstract: An OFDM communication system performs time domain channel estimation responsive to received symbols before the symbols are processed by a fast Fourier transform. The communication system generates virtual pilots from actual pilots to improve the stability and quality of channel estimation. The system generates a reference signal from the actual and virtual pilots and correlates the resulting reference signal with a signal responsive to the received symbol to generate an initial channel impulse response (CIR) and to determine statistics about the channel. In some circumstances, the resulting reference signal is correlated with a modified symbol in which the actual and virtual pilot locations are emphasized and the data locations are deemphasized. Time domain channel estimation iteratively improves on the initial CIR. The system determines channel estimates for data only symbols through averaging such as interpolation.

Abstract: A modular shelving system comprises a first upright, a second upright, first and second rails, and a rail spanner. The first upright includes a first body and a first cleat having a base portion secured in the first body. The second upright includes a second body and a second cleat having a base portion secured in the second body. Each of the first and second rails defines an upper cleat hole and a lower cleat hole. The first cleat of the first upright is slidably received in the upper and lower cleat holes of the first rail, and the second cleat of the second upright is slidably received in the upper and lower cleat holes of the second rail. The rail spanner extends between the first and second rails and includes first and second retaining claws each connected to the rail spanner.

Abstract: Assembly of a structurally sound modular shelving system includes forming an H-shaped base structure, or otherwise-shaped base structure, by releasably hooking a tie beam into a first base piece and a second base piece. A first column member is slid into the first base piece by sliding an insert tab at an end of an elongate body of the first column into a vertical passage through the first base piece. A second column member is similarly slid into a second base piece. A header member is releasably hooked into the first and second columns, the header member extending substantially horizontally between the first and second columns and substantially perpendicularly to the first and second base pieces.

Abstract: An OFDM receiver includes a fast Fourier transform processor that receives signal samples and outputs frequency domain samples corresponding to a received symbol. A delay element receives sets of frequency domain samples outputs each of the sets of frequency domain samples following a predetermined delay interval. A frequency domain channel estimator receives frequency domain samples and derives channel estimates from each of the sets of frequency domain samples. A channel estimate queue stores a sequence of channel estimates provided by the channel estimator and provides the sequence to a weighted averaging element that outputs an averaged channel estimate. A frequency equalizer outputs an equalized set of frequency domain samples responsive to the delayed set of frequency domain samples and to the averaged channel estimate.

Abstract: Assembly of a structurally sound modular shelving system includes forming an H-shaped base structure, or otherwise-shaped base structure, by releasably hooking a tie beam into a first base piece and a second base piece. A first column member is slid into the first base piece by sliding an insert tab at an end of an elongate body of the first column into a vertical passage through the first base piece. A second column member is similarly slid into a second base piece. A header member is releasably hooked into the first and second columns, the header member extending substantially horizontally between the first and second columns and substantially perpendicularly to the first and second base pieces.

Abstract: Some embodiments of the present invention provide structure that can be installed within a warehouse-type rack to convert the rack for use as a merchandise and display rack. In this manner, warehouse-type racks can be provided with a greater degree of adjustability to accommodate a larger number of shelving and product storage and display configurations. The structure installed within a warehouse-type rack can include secondary uprights connected to secondary front-rear stretchers. Preferably, the connections between the secondary uprights and the secondary front-rear stretchers are adjustable so that the secondary uprights can be secured in different positions within the warehouse-type rack. In some embodiments, the secondary uprights can be secured in different front-rear positions in the rack and/or can be secured in different vertical positions with respect to the secondary front-rear stretchers.

Abstract: A standard having a base plate that in some embodiments includes a first upturned edge, a second upturned edge, and at least one aperture. A first support can be positioned between the first upturned edge and the aperture, and can extend past a top surface of the first upturned edge. A second support can be positioned between the second upturned edge and the aperture, and can extends past a top surface of the second upturned edge. The upturned portions and supports can be dimensioned such that fasteners used to secure the standard to a surface do not interfere with elements (e.g., drywall, pegboard, display panels, and the like) covering the base plate, and/or such that the supports are at least partially recessed in a surface defined by such covering elements.

Abstract: Some embodiments of the present invention employ a modular room including a plurality of modular room components (e.g., anchor assemblies, upright assemblies, etc.). These anchor assemblies and upright assemblies can take different forms permitting assembly of a modular room or modular structure in different manners, and in some cases provide for interchangeable interior and exterior wall panels and components. In some embodiments, a bracket assembly is coupled to an substantially vertical elongated upright for improved strength and stability. Preferably, the anchor assembly has a base plate with at least one edge at an angle with respect to the rest of the base plate for additional strength. If desired, the vertical position of the upright with respect to the base plate can be adjusted. In some embodiments, one or more overhead trusses are used to stabilize the walls of a modular room.

Abstract: Some embodiments of the present invention provide structure that can be installed within a warehouse-type rack to convert the rack for use as a merchandise and display rack. In this manner, warehouse-type racks can be provided with a greater degree of adjustability to accommodate a larger number of shelving and product storage and display configurations. The structure installed within a warehouse-type rack can include secondary uprights connected to secondary front-rear stretchers. Preferably, the connections between the secondary uprights and the secondary front-rear stretchers are adjustable so that the secondary uprights can be secured in different positions within the warehouse-type rack. In some embodiments, the secondary uprights can be secured in different front-rear positions in the rack and/or can be secured in different vertical positions with respect to the secondary front-rear stretchers.

Abstract: A tag holder assembly is provided for mounting on the edges of a display shelf for retail merchandise. When the assembly is pressed against the shelf, the assembly flexes to permit members of the assembly to rotate into a locked position. This flexion gives rise to forces which reliably secure the assembly to the shelf. In one embodiment, the assembly can be removed by rotating the members to an unlocked position. The assembly can be made as a unitary device including, for example, a living hinge. Alternatively, the assembly can made as two or more separate members. The assembly can also include a projecting member that extends higher than the front surface of the shelf to prevent objects on the shelf from falling off. Significantly, any forces which the objects transmit to the assembly through the projecting member tend to lock the assembly even more securely on the shelf.

Abstract: A shelving display system comprising a conventional gondola made up of a generally horizontal base and at least two upstanding posts to which generally horizontal top and bottom tracks are attached. Support/display members, such as decorative panels, standards for shelf brackets and shelves, and partitions may be attached to the top and bottom tracks to complete the system.