Abstract: A freely rotatable micromechanical plate is achieved by employing at least three rotatable plates that are each suspended from a substrate via respective springs, and are coupled via other respective springs to at least three moveable plate attachment points, so that rotation of the rotatable plates about an axis transfers motion to the moveable plate attachment points. Respective posts couple the movement of each respective moveable plate attachment point to a moveable plate. In operation, the rotatable plates may be individually rotated, and the resulting motion of each rotatable plate is passed to its respective moveable plate attachment point. The combined motion of the moveable plate attachment points is passed to the moveable plate via the posts. Using proper control, the plate may be made to tip, tilt and piston. Advantageously, the piston motion may achieve a high vertical movement frequency response.

Abstract: When using four transmit antennas, conventional channel coding is employed for a decoupled space-time coding approach for each of a number, L, of data substreams derived from the overall source bit stream. The symbols of the data substreams, after any encoding, are processed and the resulting derivatives of the encoded data substreams, which includes at least the complex conjugate of one of the encoded symbols, are grouped to form four transmit time sequences each one spanning L symbol periods which form a transmission matrix B. Each row of the matrix corresponds to an antenna, and the elements of each row represent the samples of a temporal sequence that is emitted by the antenna in L symbol periods.

Abstract: A micro lens, or an array of micro lenses, can be formed without requiring the etching of a mesa into the substrate by deposited directly on the substrate, without any mesa each of the individual portions of the substance to be melted. The whole substrate and the portions are then conformally coated with a very thin layer of a substance, typically an adhesion promoter, e.g., hexamethyldisilazane (HMDS). The entire coated wafer is then subject to conditions which cause each of the individual substance portions to flow into a lens shape. A lens shape is achieved without requiring a mesa because the layer of adhesion promoter prevents the flowing substance from spilling in an undesired manner over the surface of the substrate.

Abstract: A packaged MEMS device containing the micro mirrors has mounted on it at least two distinct integrated circuit chips, at least one of which contains the low-voltage digital-to-analog converts and at least one of which contains the high-voltage amplifiers. The integrated circuit chips may be mounted directly to the MEMS package, or they may be indirectly mounted thereto, e.g., by being directly mounted to a multi-chip module which is in turn mounted on the package. Thus, the MEMS package is employed in a dual role, 1) that of package for the MEMS device and 2) the role of a backplane in that it contains mounting places and the wires interconnecting the MEMS device and chips or modules containing the low-voltage digital-to-analog converters and the high-voltage amplifiers.

Abstract: An arbitrary gap between the two chips of a MEMS device arranged in a flip-chip arrangement is achieved by etching into a first substrate to form mesas which act as spacers between which, or even on which, any required circuit elements are formed. Points of a layer at a first surface of the second substrate within which MEMS structures are made are bonded to the mesas of the first substrate. The second substrate is then removed, leaving the structures bonded to the mesas. The mesas may be formed by placing a hard mask, such as silicon oxide, which defines the desired pattern of mesas on the first substrate, and then etching the unmasked portion of the substrate using a mixture of potassium hydroxide (KOH) with isopropanol (IPA) or, tetramethyl ammonium hydroxide (TMAH) mixed with a surfactant, e.g., nonylphenol ethoxy ether or other equivalent compounds.

Abstract: In a MIMO system the signals transmitted from the various antennas are processed so as to improve the ability of the receiver to extract them from the received signal even in the face of some correlation. More specifically the number of bit streams that is transmitted simultaneously is adjusted, e.g., reduced, depending on the level of correlation, while multiple versions of each bit stream, variously weighted, are transmitted simultaneously. The variously weighted versions are combined to produced one combined weighted signal. The receiver processes the received signals in the same manner as it would have had all the signals reaching the receive antennas been uncorrelated.

Abstract: In a TDMA system a multifunction control channel is employed that carries data used for implementing channel access functionality for users and is also employed at the remote terminals in the performance of modem functionality. In other words, information necessary to accurately receive data on the user traffic channels is obtainable by processing the multifunction control channel. This is achieved by arranging the broadband channel of the TDMA system as a repeating frame having time slots in which at least one time slot is reserved for use as the multifunction control channel, and the data that is transmitted on the multifunction control channel is encoded using a spread spectrum format. To this end the data carried on the multifunction control channel is encoded in a way that uses each symbol of the multifunction control channel as if it were a so-called spread spectrum “chip”.

Abstract: A precise fiber array is formed using a chuck to tightly hold as an array with hexagonal packing a group of precision ferrules into ones of which is inserted and bonded a fiber end. The bonding is typically performed by gluing the fiber into the ferrule. The ferrules may also be bonded to each other. Once the ferrules are bonded together, the chuck may be removed. The terminating end of the fibers may be polished. Alternatively, cleaved terminating fiber ends may be employed, with the various terminating ends being coordinated, e.g., by an optical flat. The ferrules may have a tip and a conical entrance. The chuck may hold the ferrules in a straight orientation. The fiber terminating faces of all of the ferrules may be substantially coplanar. The ferrules may be arranged in a hexagonal configuration.

Abstract: In a wireless communication system, the constellation mapping scheme employed may be changed on a per-time-slot basis, i.e., from time slot to time slot, so that the constellation used to encode the symbols of each time slot may be different for each time slot within a single frame and may be different for a particular time slot in different consecutive frames. In other words, several constellation mapping schemes are available, with each providing the ability to transmit a different number of bits per symbol, and the particular constellation mapping scheme employed for any time slot need be selected for that time slot only. The ability to use any particular constellation mapping scheme is dependent on the current channel quality. The particular constellation mapping used for the user data of the time slot may be indicated in the preamble of the time slot.

Abstract: Signals are developed for use in a wireless system with multiple transmit and multiple receive antennas so that even in the face of some correlation the most open-loop capacity that can be achieved using a substantially open-loop system with a channel of that level of correlation is obtained. In accordance with the principles of the invention, the signals transmitted from the various antennas are processed so as to improve their ability to convey the maximum amount of information. More specifically, the data to be transmitted is divided into M+1 substreams, where M is the number of transmit antennas. Each transmit antenna is supplied with a combination signal that is made up of a weighted version of a common one of the substreams and a weighted version of a respective one of the substreams that is supplied uniquely for that antenna, so that there are M transmit signals. A receiver having N antennas receives the M transmit signals as combined by the channel and reconstitutes the original data therefrom.

Abstract: The beams between a MEMS device and an input source or an output, e.g., a fiber bundle, are caused to be closer to each other at the MEMS device than at the fiber bundle. This can be achieved in a variety ways. This may be achieved a) when each fiber is associated with a respective micro lens of a micro lens array, by insuring that there is a different distance between the centers of adjacent micro lenses than there is for the centers of their corresponding adjacent fibers, b) when the fibers are terminated by collimators, the direction of the collimators is adjusted to point the beams in a converging manner and c) by employing an optical system that changes the direction of various ones of the beams may be interposed between a) the fiber bundle and b) the corresponding MEMS device.

Abstract: In an all optical switch an imaging system is interposed between the micro lens array and the moveable micro mirrors of a MEMS device to which, or from which, the light beams are directed. This causes an image of the micro lens array to be formed at the MEMS device, or vice-versa, thus effectively eliminating the distance between the micro lens array and the MEMS device. The imaging system may be a telecentric system. The size of the arrangement may be reduced by compacting the optical path, e.g., using appropriate conventional mirrors, and/or employing folded arrangements, i.e., arrangements in which there is only one MEMS device stage that does double duty for both input and output through the use of at least one conventional mirror. The overall system is arranged to account for any inversions introduced.

Abstract: Problems with source followers employed in active arrays are alleviated by employing a differential amplifier for each element of the active array. However, instead of including an entire differential amplifier within each element, part of the differential amplifier structure is shared among each sensor element connected to a particular column. For example, the differential amplifier may be a differential pair operational transconductance amplifier (OTA) which is connected using a feedback configuration. However, instead of including an OTA within each sensor element of the array, part of the OTA structure is shared among each sensor element connected to a particular column. Although gains greater than one are achievable by employing the differential amplifier with a feedback network, to avoid introducing fixed pattern noise, substantially unity gain is often preferred. Furthermore, the shared differential amplifier model of array reading may be employed for any active array readout application, e.g.

Abstract: A precise fiber array may be formed by employing an array of pins into ones of the resulting interstices of which is inserted and bonded, e.g., glued, a fiber end. Such an array may be made by employing a chuck, at least initially, to tightly hold as an array a group of pins, e.g., metal, ceramic, or plastic pins. Thereafter, a fiber end is inserted and bonded into ones of the interstices formed by the resulting gaps, i.e., the interstices, between the pins. The pins may also be bonded to each other. If so, once the pins are bonded together, the chuck may be removed. The terminating end of the fibers may be polished. Alternatively, previously cleaved terminating fiber ends may be employed, with the various terminating ends being coordinated, e.g., by an optical flat or other surface which is placed at, or adjacent to, the fiber terminating end of the pin array.

Abstract: Without intercell coordination on a per communication request basis, channel assignment can be efficiently performed by developing for each cell, or a sector thereof when the cells are sectorized using directional antennas, a priority list of groups of channels, and selecting a channel to be assigned in response to a request for service from the highest priority group which has available channels at the time of the service request. The priority lists are developed based on various interference measurements that are made. The priority lists tend to remain the same for relatively long periods of time. However, periodically, the priority lists should be redetermined to insure that the best lists are being employed. For example the lists may need to be changed due to new construction or to seasonal vegetation changes which may affect the interference experienced in the system. Advantageously, system capacity under peak concentrated load conditions may increase.

Abstract: Problems caused by a nonuniform processing profile are avoided by altering the area to be processed so as to compensate for the processing profile. More specifically, with regard to etching, problems caused by a nonuniform etch profile can be avoided by altering the mask employed in specifying the etch area so as to compensate for the etch profile. Nonuniform parameters of interest of structures which result from a nonuniform etch profile during the etching of a mask in which all the structures were identical can be avoided for by altering the mask employed in specifying the etch area so as to compensate for the etch profile. The mask is changed in a manner that is inversely proportional to the etch profile for each particular structure characteristic that determines the parameter of interest for which uniformity is desired.

Abstract: Using an imaging system, an optical MEMS devices is imaged so that in combination with an actual one or more other optical MEMS devices, or images thereof, a single virtual optical MEMS device is formed that has the size of each of the optical MEMS devices combined. The physical size of the arrangement may be reduced by compacting the optical path, e.g., using appropriate conventional mirrors, and/or employing folded arrangements, i.e., arrangements in which there is only one MEMS device stage that does double duty for both input and output through the use of at least one conventional mirror. The imaging system may reproduce the angle of reflection of the light from the micro mirror, e.g., using a telecentric system. A prism may be employed to align the various optical MEMS devices, or images thereof.

Abstract: In a system in which the modulation scheme employed may change on a per-time-slot basis, a user's available data rate may change even if the user maintains the same number of time slots, because the capacity of the user's time slots may change. If one or more such changes in modulation scheme occurs, the data rate available to the user may no longer match his current data rate needs. Therefore, a method is disclosed for determining the number of time slots to assign to a user as a function of the user's current data rate requirement and the actual current cumulative data rate of the time slots currently assigned to the user. The user data rate requirement may further be a function of a quality of service (QoS) contracted for by the user.

Abstract: A two layered segmentation technique coupled with a two layer error detection technique is used to implement the wired to wireless network interface. A wireless network divides network layer packets from a wired network into radio data link packets, and the information within the radio data link packets is divided into portions that can be placed into time slots. Error detection is performed on each of the time slots and also at the radio data link packet level to determine if there is an error within the radio data link packet. Errors detected in any radio data link packet only requires retransmission of the radio data link packet in which the error was detected, and, advantageously, do not require retransmission of the entire network layer packet as would have been required in a system that mapped directly from network layer packets to time slots.

Abstract: A technique is described for producing field recognition scores that vary according to the position of the errors. In particular, a value-based score for a recognition result is determined from both the individual character recognition scores and an “error value” that is associated with each character position of the recognition result. In general, this value-based score is computed by adding the error value for each character position of the recognition result. As illustration, an OCR system for scanning checks is adapted to produce field recognition scores that reflect economic value. In this approach, an error in the leftmost digit is “worth” much more than an error in the rightmost digit.