Showing papers by "Motorola published in 1995"

Combined differential and common-mode scattering parameters: theory and simulation

Abstract: A theory for combined differential and common-mode normalized power waves is developed in terms of even and odd mode impedances and propagation constants for a microwave coupled line system. These are related to even and odd-mode terminal currents and voltages. Generalized s-parameters of a two-port are developed for waves propagating in several coupled modes. The two-port s-parameters form a 4-by-4 matrix containing differential-mode, common-mode, and cross-mode s-parameters. A special case of the theory allows the use of uncoupled transmission lines to measure the coupled-mode waves. Simulations verify the concept of these mixed-mode s-parameters, and demonstrate conversion from mode to mode for asymmetric microwave structures. >

MMSE decision-feedback equalizers and coding. I. Equalization results

Abstract: The minimum mean-squared-error decision-feedback equalizer (MMSE-DFE) has properties that suggest that it is a canonical equalization structure for systems that combine equalization with coded modulation. The structure and performance of the MMSE-DFE are succinctly derived using linear-estimation-theoretic principles in this first part of this two-part paper. The front-end of the MMSE-DFE, called the "mean-square whitened matched filter" (MS-WMF), is preferable in some ways to a matched filter or a whitened matched filter as a canonical receiver front end. In a coded system, the feedback filter of the MMSE-DFE may be implemented in the transmitter using precoding. The MMSE-DFE can perform significantly better than a zero-forcing decision-feedback equalizer, particularly at moderate-to-low SNR's and on severe-ISI channels. The MMSE-DFE is biased. The optimum unbiased MMSE-DFE is the MMSE-DFE with the bias removed. Removing bias improves error probability, but reduces the SNR to SNR/sub MMSE-DFE,U/=SNR/sub MMSE-DFE/-1. It is shown that this SNR relationship is a particular case of a very general result and that SNR/sub MMSE-DFE,U/ gives a more realistic estimate of SNR. The results are extended to partial response equalization and to equalization with correlated inputs in an appendix. >

Personal locator system

Abstract: A system and method for locating a portable locator device in a communications network. The portable locator unit (PLU) (4) is activated either by an external signal (62) generated in response to remote activation source, such as a subscriber (6, 8) or PLU detector (106, 108), or by an internal activation signal triggered e.g. by the wearer. Once activated, the PLU (4) transmits a location signal (66). This location signal (66) is received by one or more network service nodes (20, 22, 24) which forward the information along with identifying service node information to a network location processor (26, 28). After having determined the location of the PLU (4) from the received information, the network location processor (26, 28) forwards this information to a designated source, such as the requesting subscriber or other authorized user (6, 8).

A tutorial on MPEG/audio compression

Abstract: This tutorial covers the theory behind MPEG/audio compression. While lossy, the algorithm can often provide "transparent", perceptually lossless compression, even with factors of 6-to-1 or more. It exploits the perceptual properties of the human auditory system. The article also covers the basics of psychoacoustic modeling and the methods the algorithm uses to compress audio data with the least perceptible degradation. >

Enhanced mobility MOSFET device and method

Abstract: An enhanced mobility MOSFET device (10) comprises a channel layer (12) formed on a monocrystalline silicon layer (11). The channel layer (12) comprises an alloy of silicon and a second material with the second material substitutionally present in silicon lattice sites at an atomic percentage that places the channel layer (12) under a tensile stress.

Minimisation of the peak to mean envelope power ratio of multicarrier transmission schemes by block coding

Abstract: A block coding scheme for the reduction of the peak to mean envelope power ratio of multicarrier transmission schemes is described. The principle of the scheme is illustrated with the specific example of a four carrier signal. The potential of the technique is investigated and it is shown that the application of a 1/2 rate code could typically result in a peak to mean envelope power ratio of around 3 dB. The development of the technique in terms of the selection of suitable sets of code words based on Shapiro-Rudin sequences, Golay complementary sequences and other larger sets of code words is investigated. However, it is shown that none of these code sets are ideal.

Multi-channel digital transceiver and method

Abstract: A multi-channel digital transceiver (400) receives uplink radio frequency signals and converts these signals to digital intermediate frequency signals. Digital signal processing, including a digital converter module (426), is employed to select digital intermediate frequency signals received at a plurality of antennas (412) and to convert these signals to baseband signals. The baseband signals are processed to recover a communication channel therefrom. Downlink baseband signals are also processed and digital signal processing within the digital converter module (426) up converters and modulates the downlink baseband signals to digital intermediate frequency signals. The digital intermediate frequency signals are converted to analog radio frequency signals, amplified and radiated from transmit antennas (420).

Electronic transport studies of bulk zincblende and wurtzite phases of GaN based on an ensemble Monte Carlo calculation including a full zone band structure

Abstract: The ensemble Monte Carlo technique including the details of the first four conduction bands within the full Brillouin zone is used to calculate the basic electronic transport properties for both zincblende and wurtzite crystal phases of bulk gallium nitride. The band structure throughout the Brillouin zone is determined using the empirical pseudopotential method. Calculations of the electron steady‐state drift velocity, average energy, valley occupancy and band occupancy in the range of electric fields up to 500 kV/cm are presented. It is found that the threshold electric field for intervalley transfer is greater and that the second conduction band is more readily occupied in wurtzite than in zincblende GaN over the range of electric fields examined here.

Method and system for encoding a book for reading using an electronic book

Abstract: A method and system for encoding a book for reading by an electronic book having an internal machine-readable dictionary includes receiving data representative of text and graphical information of the book. First machine-readable data representative of a plurality of words are encoded to provide a customized dictionary which augments the internal machine-readable dictionary. Second machine-readable data representative of the text are encoded. The second machine-readable data includes a plurality of pointers which point to a corresponding plurality of words in the machine-readable dictionary and the customized dictionary. Third machine-readable data representative of the graphical information are encoded. An access authorization level is provided for reading at least one of the first machine-readable data, the second machine-readable data, and the third machine-readable data.

Noise reduction filters for dynamic image sequences: a review

Abstract: In this paper, a thorough review is presented of noise reduction filters for digital image sequences Detailed descriptions of several spatiotemporal and temporal noise reduction algorithms are provided To aid in comparing between these different algorithms, we classify them based on their support (ie, 3-D or 1-D filter) and whether or not motion compensation is employed Several algorithms from each of the four categories are implemented and tested on real sequences degraded to various signal-to-noise ratios These experimental results are discussed and analyzed to determine the overall advantages and disadvantages of the four general classifications, as well as, the individual filters >

Method and apparatus for communicating summarized data

Abstract: In a main embodiment, select and summary (S&S) indices (213, 228) are used to provide user flexibility in reviewing and requesting otherwise filtered data. Both the user's remote unit (201) and communication server (220) maintain S&S indices containing identifying (summary) information about data which has not been fully transferred between the communication server and remote unit. As new data is filtered for transfer (704-706), identifying information is captured (710) for any non-qualifying data by either a host unit or the communication server. This information is stored (714) in the communication server's S&S index, and transferred (718) via update messaging to the remote unit. When reviewing its updates or S&S index, the user may request (722) such of the data that it desires partial or full transfers of for further review. Thus, a cost efficient review mechanism is provided to users for determining whether to transfer data that otherwise fails selected filter parameters.

Wireless messaging system with electronic mail replication

Abstract: A wireless messaging system (10) is provided that comprises a wireless message distribution system (12) which receives wireless messages from telephones (14), computer message entry program (16) or telephone-assisted service terminals (18). The wireless messages are sent through a radio frequency transmission (20) to users (22). In addition, the wireless messages are replicated and sent to a wireless message gateway server (24). The wireless message gateway server (24) assembles electronic mail messages including the wireless message and transmits the electronic mail messages to electronic mail networks (26), (28), or (30) such that the user (22) may access his wireless messages through his electronic mailbox within a customer electronic mail system (32).

Routing subject to quality of service constraints in integrated communication networks

Abstract: With increasingly diverse QOS requirements, it is impractical to continue to rely on conventional routing paradigms that emphasize the search for an optimal path based on a predetermined metric, or a particular function of multiple metrics. Modern routing strategies must not only be adaptive to network changes but also offer considerable economy of scope. We consider the problem of routing in networks subject to QOS constraints. After providing an overview of prior routing work, we define various QOS constraints. We present a call architecture that may be used for QOS matching and a connection management mechanism for network resource allocation. We discuss fallback routing, and review some existing routing frameworks. We also present a new rule-based, call-by-call source routing strategy for integrated communication networks. >

Method and apparatus for personal attribute selection and management using a preference memory

Abstract: An application device (401) is connectable with a donor device (541) such as a portable memory card (560) or widely accessible central database (550). The donor device (541) stores and provides preferences to the application device (401). The donor device (541) contains a reference preference memory capable of storing preferences for a particular user. A controller (450) accesses the donor device to obtain preferences that pertain to the particular user under certain conditions and stores preferences obtained from the donor device in the session preference memory (490) of the application device (401) for use in a session by the particular user.

Universal multimedia access device

Abstract: A universal multimedia access apparatus for accessing any of a plurality of multimedia applications provided by a multimedia network. The universal multimedia access apparatus accesses a predetermined one of the plurality of multimedia applications using an application-specific module interfaced thereto, the application-specific module being selected from a plurality of application-specific modules. The universal multimedia access apparatus comprises a transceiver and a processing unit. The transceiver communicates multimedia information between the multimedia network and the application-specific module, and communicates with the multimedia network in any one of a plurality of communication modes. The processing unit is operative to identify the application-specific module interfaced thereto and the predetermined one of the plurality of multimedia applications associated with the application-specific module, and operative to command the transceiver to communicate with the multimedia network in a mode associated with the predetermined one of the plurality of multimedia applications.

Method for providing communication services based on geographic location

Abstract: Communication services can be controlled within geographic areas (126) by a communication resource controller (101). This occurs, when the communication resource controller (101) receives the location of a particular communication unit (102, 103) and a particular service request. Having this information, the communication resource controller (101) accesses a database (124) and determines whether that particular service request is restricted in the area that the unit is located. If the service is restricted in that area, the communication unit's (102, 103) request is denied.

Method for secure network access via message intercept

Abstract: Security is provided for an inside network (14) by a security host (26). Connection request messages sent from source hosts (22) in an outside network (12) are intercepted (94) in the security host (26) and prevented from being transmitted on the inside network (14). The user of the source host (22) then establishes a connection (78) to the security host (26) where a dialog session (80, 98, 100) occurs to confirm the user's authenticity and authorization. After the user is confirmed, the intercepted connection request message is released (116) for transmission on the inside network (14) where the intended application service will respond and a communication session will commence.

Method and apparatus for authentication in a communication system

Abstract: A method and apparatus for authenticating a roaming subscriber. In a preferred embodiment, a subscriber receives a challenge (305) that is in a format of a local authentication protocol, and determines (310) whether the local authentication protocol is the subscriber's home system authentication protocol. If it is not, the subscriber converts the challenge into a format (e.g., bit length) compatible (325) with its home system authentication protocol, and processes the converted challenge with the subscriber's secret key and authentication algorithm into an authentication response (330). The authentication response is converted (335) to be compatible with the local authentication protocol, and transmitted (340) to a local system communication unit. The challenge and response is then forwarded to the subscriber's home system (345) for similar conversion and processing, and the subscriber's response is compared against a home system generated response (355).

Method and apparatus for conveying a communication signal between a communication unit and a base site

Abstract: A communication system (100) employs a method (600) and apparatus (101) for conveying a communication signal between a communication unit (105) and a base site (101) that services a sectorized coverage area (103). The communication unit (105) transmits an uplink communication signal (113) to the base site (101). The base site (101) receives (603) the uplink communication signal (113) and determines (605) an approximate location of the communication unit (101) within a first portion (111) of a sector (108) of the sectorized coverage area (103). A downlink communication signal is then transmitted (609, 613) to the communication unit (105) based on the approximate location of the communication unit (105) using an antenna structure that produces a beamwidth (117) narrower than an angular width of the sector (108).

Data processing system for performing a debug function and method therefor

Abstract: A data processor (3) executes a real time trace function which allows an external development system (7) to dynamically observe internal operations of data processor (3) without assuming a type or availability of an external bus and without significantly impacting the efficiency and speed of the data processor (3). A debug module (10) of data processor (3) provides a parallel output port for providing internal operating information via a DDATA signal and a PST signal. The DDATA signal provides data which reflects operand values and the PST signal provides encoded status information which reflects an execution status of a central processing unit 92). Furthermore, the DDATA signal also provides captured instruction address program flow changes to allow external development system (7) to trace an exact program flow without requiring an externally visible address bus or an externally visible data bus.

Method of providing an alert of a financial transaction

Abstract: A radio system user (126) is alerted (129) as to the occurrence of a financial transaction by a customer (118). Data (122) is obtained from the customer (118) and used to identify a radio system user (126), who is authorized to conduct the financial transaction. A message, indicative of the financial transaction, is automatically provided to a radio system and broadcast (129) to the radio system user (126), thereby alerting the user (126) to the financial transaction.

System having virtual session manager used sessionless-oriented protocol to communicate with user device via wireless channel and session-oriented protocol to communicate with host server

Abstract: A communication system includes a virtual session manager (225) for establishing and maintaining a sessionless communication path with a user device (201) on the one hand and a session-oriented communication path with a host system (231). The session-oriented connection with the host system permits normal access to, e.g., LAN-based applications, while the virtual session between the virtual session manager and user permits this access to be carried out remotely without the expense of a dedicated/circuit-switched or other session-oriented connection.

Electronic book having highlighting feature

Abstract: An electronic book includes a book-shaped housing having a first housing member pivotably connected to a second housing member to open and close in a book-like manner. A touchscreen displays a page of the text represented by the machine-readable data. A user-initiated event selecting a portion of the text is received by the touchscreen. The touchscreen displays the portion of the text in a highlighted form. The processor stores an indicator of the portion of the text to be highlighted in the removable machine-readable storage medium to remain with the text when the removable machine-readable storage medium is removed from the electronic book.

Process for underfilling a flip-chip semiconductor device

Abstract: A flip-chip semiconductor device (70) is formed by mounting a semiconductor die (20) to a wiring substrate (30). The wiring substrate includes a hole (39). An underfill encapsulation material (52) is dispensed around an entire perimeter of the semiconductor die. The underfill encapsulation material then flows toward the center of the die, expelling any trapped air through hole (39) of the wiring substrate to avoid voiding. By providing a method which utilizes an entire perimeter dispense, manufacturing time of the underfilling step is significantly reduced. At the same time, a uniform fillet is formed and the formation of voids in the underfill encapsulation material is avoided due to the presence of hole (39) in the wiring substrate. Multiple die (100) can also be underfilled using a single dispensing operation in accordance with the invention.

Communications device responsive to spoken commands and methods of using same

Abstract: A communications device (20) that is responsive to voice commands is provided. The communications device (20) can be a two-way radio, cellular telephone, PDA, or pager. The communications device (20) includes an interface (22) for allowing a user to access a communications channel according a control signal and a speech-recognition system (24) for producing the control signal in response to a voice command. Included in the speech recognition system (24) are a feature extractor (26) and one or more classifiers (28) utilizing polynomial discriminant functions.

Method and apparatus for communicating an optimized reply

Abstract: For optimized reply, when sending a reply (902) in a first embodiment a remote communication unit's controller (206) generates a delta between a preceding message and the reply message, and forms an optimized reply (904) using the delta and an identifier of the preceding message. On receiving the optimized reply, the communication server uses the data unit identifier to retrieve (910) the preceding message from a further server (e.g., the post office mailbox of the user associated with the remote unit), reconstructs (914) the full reply from the retrieved message and the delta, and forwards (916) the full reply to the addressee. When receiving a reply for the remote unit (918), an index is preferably maintained by both units of mail stored at the remote unit. From this index a preceding message forming part of the reply is identified (920). An optimized reply is then similarly formed (922) and sent to the remote unit.

Low profile exposed die chip carrier package

Abstract: An integrated circuit package (10) comprises a semiconductor die (12), and a substrate (14) having a through-cavity opening (22) for receiving the semiconductor die. The bottom side of the substrate has solder pads (24) arranged as a peripheral pad grid array. The semiconductor die is wire bonded (26) to the to the top side of the substrate. An encapsulant (16) seals the top surface of the semiconductor die and circuitry, and portions of the top side of the substrate. The bottom surface of the semiconductor die remains exposed to the atmosphere, eliminating moisture-related die attach delamination issues and improving heat transfer away from the semiconductor die. Furthermore, the reduced contribution of the semiconductor die to overall package height results in an ultra low profile package.

Method, device and router for providing a contention-based reservation mechanism within a mini-slotted dynamic entry polling slot supporting multiple service classes

Abstract: The entry polling (EP) method (900) of the present invention primarily incorporates two types of polling: contention based and standard polling. The present invention provides several advantages over present polling approaches. EP slots allow multi-priority users to compete for access into the standard polling scheme. The reservation channel is efficiently used by dynamically adjusting the frequency of contention slots based on system dynamics and dynamically changing the number of contention minislots for each service category within a contention slot with the case of sending only one minislot per slot. The channel is assigned primarily to active users. Pipeline polling is also incorporated, thus providing full use of the upstream channel. Since the local state information is provided by the user, the central controller may allow multiple variable length packets to be sent.