Abstract: A system and method for determining operating parameters to control a communication rate for an adaptive rate communication system includes a transmitter (101) to transmit a signal (135) through a channel (142) to a receiver (103). The receiver (103) determines operating parameters based on, among other things, an effective bit rate and a percentage of speech in the signal. The receiver conveys the operating parameters to the transmitter for use in subsequent communications from the transmitter (101) to the receiver (103).

Abstract: A semiconductor junction (13) is represented as a junction capacitance (21) in parallel with a junction resistance (23) and junction inductance (22). The junction capacitance, junction resistance and junction inductance are functions of the voltage across the semiconductor junction and are determined using a probability of charge stored across the semiconductor junction. Junction parameters are determined with parameter extraction processes. A circuit simulation tool is used to simulate the performance of a circuit that includes the semiconductor junction. Accordingly, diode junctions are more accurately modeled above their built-in potential and below their reverse break-down voltage.

Abstract: A gate quality oxide-compound semiconductor structure (10) is formed by the steps of providing a III-V compound semiconductor wafer structure (13) with an atomically ordered and chemically clean semiconductor surface in an ultra high vacuum (UHV) system (20), directing a molecular beam (26) of gallium oxide onto the surface of the wafer structure to initiate the oxide deposition, and providing a second beam (28) of atomic oxygen to form a Ga.sub.2 O.sub.3 layer (14) with low defect density on the surface of the wafer structure. The second beam of atomic oxygen is supplied upon completion of the first 1-2 monolayers of Ga.sub.2 O.sub.3. The molecular beam of gallium oxide is provided by thermal evaporation from a crystalline Ga.sub.2 O.sub.3 or gallate source, and the atomic beam of oxygen is provided by either RF or microwave plasma discharge, thermal dissociation, or a neutral electron stimulated desorption atom source.

Abstract: A method and apparatus for protecting software objects from external modification is described. A cryptographic seal protects the object at the object level and also supports secure inter-object communication. A software object (101) is packaged in a crypto seal (103), which provides a cryptographic code hasher (105) for performing a cryptographic form of hashing on the code of object (101), a crypto seal communications authenticator (107) which authenticates communications received by object (101), a crypto seal encryptor (108) which encrypts communications sent by the object (101), a challenge manager (106) which causes the cryptographic code hasher (105) to perform its hashing function on the code of object (101) periodically and on demand when a challenge message is received, and a communications interface (109) which controls inter-object communication. A system (100) which employs crypto sealed objects includes a crypto seal coordinator (119).

Abstract: A secure computer system (100) includes a host processor (105) for communicating a datum to a trusted bus (101). A bridge (125) connects the trusted bus (101) to an untrusted bus (102). The bridge (125) conveys the datum from the trusted bus (101) to the untrusted bus (102). A bus access monitor (200) is coupled to the trusted bus (101) and the untrusted bus (102). The bus access monitor (200) performs a method (1000, FIG. 10) for securely monitoring the untrusted bus (102), and asserting an alarm signal when address information associated with the datum fails to compare with predetermined address information. Additionally, the host processor (105) performs a method (300, FIG. 3) for self-testing the bus access monitor.

Abstract: Classifiers (110) and a comparator (112) perform an identification method (400) to identify a class as one of a predetermined set of classes. The identification method is based on determining the observation costs associated with the unidentified class. The identification method includes combining models representing the predetermined set of classes and the unidentified vectors representing the class. The predetermined class associated with the largest observation cost is identified as the class. Additionally, a unique, low-complexity training method (300) includes creating the models which represent the predetermined set of classes.

Abstract: A wide bandwidth frequency multiplier (48) multiplies a first frequency of an input signal (52) to generate an output signal (54) having a second frequency. The multiplier (48) includes first stage doubler (56). The doubler (56) includes a lumped element power splitter (62), a push-push amplifier (80), and a combining junction (96). The power splitter (62) splits the input signal (52) into first and second signals (70, 72) that are balanced in phase. A series resistive element (86) maintains amplitude balance between the first and second signals (70, 72). First and second feedback circuits (166, 184) are integrated with first and second transistors (164, 182) so that the push-push amplifier (80) operates over wide bandwidth. In addition, the multiplier (48) includes a second stage doubler (58) configured similar to the first stage doubler (56) for producing an output signal (54) that is quadruple the frequency of input signal (52).

Abstract: A secure terminal includes a host (105) and slaves (125) which send and receive messages via a peripheral component interconnect (PCI) bus (130). The host allows slaves to receive messages from the host and send messages to the host. The host prevents slave-to-slave communication of messages. The host and each slave include interface logic (120) coupled to the PCI bus and a memory (200) for coupling a processor (110) to the interface logic (120). Each dual-port RAM (200) includes a first memory portion for receiving messages from a sender and a second memory portion for storing messages to be transmitted to a receiver.

Abstract: A method of evaluating a cryptosystem to determine whether the cryptosystem can withstand a fault analysis attack, the method includes the steps of providing a cryptosystem having an encrypting process to encrypt a plaintext into a ciphertext, introducing a fault into the encrypting process to generate a ciphertext with faults, and comparing the ciphertext with the ciphertext with faults in an attempt to recover a key of the cryptosystem.

Abstract: A data processing system (20) schedules the allocation of a common bus (26), used by multiple service requesters (32). The system (20) creates a plurality of service request levels (44) and assigns each service requester (32) to one of the plurality of request levels (44). Services of the common bus (26) are provided to all service requesters (32) assigned to a first service request level (44) for each instance of providing service to one of the service requesters (32) assigned to a second service request level (44). The method then again provides services of the common bus (26) to all service requesters (32) assigned to the first service request level (44) for a single instance of providing service to one of the second level requesters (32).

Abstract: A programmable crypto processing system (10) includes several processing resources (14, 16, 26) implemented on a single ULSI die. The processing system is both key and algorithm agile allowing for simultaneous execution of a variety of cryptographic programs through the use of background staging of the next program and context (key and state) during execution of a current program. The programmable crypto processing system includes a programmable crypto processor (17) for processing data units in accordance with a channel program, a crypto controller (11) for identifying a channel program, two interface processors (13, 15) for asynchronously receiving and transferring data units from and from an external host. Data units identify a particular channel program, and are processed in a selected processing engine in accordance the identified channel program.

Abstract: A method and apparatus for improving the quality and transmission rates of speech is presented. Upon connection of a call with a receiving terminal, a communication unit (12, 26, 28, 42, 57, 54, 60) reads a dynamic user-specific speech characteristics model (SCM) table and user-specific input stimulus table and sends them to an appropriate point in the connection path with the receiving terminal. As normal voice conversation begins, the user's speech is collected into speech frames. The speech frames are compared to input stimuli entries in the user-specific input stimulus table, and are used to calculate SCMs which are compared to dynamic user-specific SCM table entries in the dynamic user-specific SCM table to generate an encoded bit stream. Simultaneously, speech characteristics statistics are collected and analyzed in view of multiple available generic SCMs to update and improve the dynamic user-specific SCM table during the progress of the call to closely track changes in the user's voice.

Abstract: An electro-conductive ultraviolet light transmitting Ga.sub.2 O.sub.3 material (10) with a metallic oxide phase is deposited on a GaAs substrate or supporting structure (12). The Ga.sub.2 O.sub.3 material or thin layer comprises a minor component of metallic IrO.sub.2. The Ga.sub.2 O.sub.3 thin layer may be positioned using thermal evaporation (106) of Ga.sub.2 O.sub.3 or of a Ga.sub.2 O.sub.3 containing a compound from an Iridium crucible (108). Alternatively, the Ir may be co-evaporated (110) by electron beam evaporation. The electro-conductive ultraviolet light transmitting material Ga.sub.2 O.sub.3 with a metallic oxide phase is suitable for use on solar cells and in laser lithography.

Abstract: An K-band amplifier circuit (10) with two samplers (12, 18) coupled to detectors (22, 26) that detect an input and an output RF signal level. These two reference signals are provided to a differential gain control circuit (24) which is coupled to one or more variable gain amplifier (VGA) (14) stages. The VGAs compensate for the gain of an entire chain of amplifiers (16). When the individual amplifier gains vary for any reason, (i.e., process, temperature effects or end of life degradation) the variation in gain causes higher or lower levels of detected output reference signals for a given RF input signal. The gain control circuit (24) drives the VGA (14) up or down as appropriate. By maintaining a constant offset in input and output reference control signals, the gain control circuit (24) drives the amplifier chain (16) to a constant gain.

Abstract: A dynamic network security system (20) responds to a security attack (92) on a computer network (22) having a multiplicity of computer nodes (24). The security system (20) includes a plurality of security agents (36) that concurrently detect occurrences of security events (50) on associated computer nodes (24). A processor (40) processes the security events (50) that are received from the security agents (36) to form an attack signature (94) of the attack (92). A network status display (42) displays multi-dimensional attack status information representing the attack (92) in a two dimensional image to indicate the overall nature and severity of the attack (92). The network status display (42) also includes a list of recommended actions (112) for mitigating the attack. The security system (20) is adapted to respond to a subsequent attack that has a subsequent signature most closely resembling the attack signature (94).

Abstract: An single event upset (SEU) tolerant system for detecting and correcting an SEU includes a decision element (200) for receiving a plurality of outputs (120) from a plurality of signal generators (105) and producing an output (130) therefrom. The decision element includes voters which provide two levels of voting for the plurality of redundant outputs (120). First-level voters (300) provide intermediate voted outputs (315) which are received by a second-level voter to determine an output (130). An output disabler (400) determines when an output is provided external to the decision element. A plurality of comparators (210) receive intermediate voted outputs (315) from first-level voters and compare with a plurality of outputs from a plurality of signal generators to determine upset detected signals (125). An upset detected signal controls the selection of feedback for an element having experienced an SEU.

Abstract: Apparatus and a method are described for providing for multiple secure functions in a host or wireless radiotelephone. Access to the functionality of the radiotelephone is provided by means of a smart card or security token features contained therein. The determination of the secure function which is accessed is determined by encrypted credential information carried in the smart card. The smart card may be used for numerous applications, but is particularly useful in conjunction with radiotelephone devices having a plurality of secure communication levels. The radiotelephone device will activate the secure levels based on the security level algorithm carried in the smart card.

Abstract: Apparatus and a method are described for providing a security token. The security token may be used for numerous applications, but is particularly useful in conjunction with radiotelephone devices having secure functions. In accordance with the invention the user must insert a PIN and utter sounds. The radiotelephone device will activate the secure functions only if the PIN is correct and the sounds uttered are authenticated against voice feature vectors stores it the token.