Showing papers by "Motorola published in 1983"

Method of producing titanium nitride MOS device gate electrode

Abstract: An MOS device having a gate electrode and interconnect of titanium nitride and especially titanium nitride which is formed by low pressure chemical vapor deposition In a more specific embodiment the titanium nitride gate electrode and interconnect have a silicon layer thereover to improve oxidation protection

Ceramic bandpass filter.

Abstract: Un filtre ceramique passe-bande unique (100) se compose d'un bloc dielectrique (130) possedant un ou plusieurs trous (101-106) s'etendant de sa surface superieure jusqu'a sa surface inferieure et possedant egalement des electrodes d'entree et de sortie (124, 125) disposees chacune sur le bloc dielectrique a une distance predeterminee d'un trou correspondant. A single bandpass ceramic filter (100) comprises a dielectric block (130) having one or more holes (101-106) extending from its upper surface to its lower surface and also having electrodes of inlet and outlet (124, 125) each disposed on the dielectric block at a predetermined distance from a corresponding hole. Le materiau dielectrique est de preference en ceramique comprenant du BAO, du TuO2 et du ZrO2. The dielectric material is preferably ceramic comprising BAO, the TuO2 and ZrO2. Lorsqu'il n'y a qu'un trou dans le bloc dielectrique, les electrodes d'entree et de sortie peuvent etre disposees autour de ce trou. When there is a hole in the dielectric block, input and output electrodes can be disposed around the hole. Si il y a deux ou plusieurs trous dans le bloc dielectrique, une electrode peut etre disposee a proximite du trou a une extremite et l'autre electrode peut etre disposee a proximite du trou a l'extremite opposee du bloc dielectrique. If there are two or more holes in the dielectric block, an electrode can be disposed near the hole at one end and the other electrode can be disposed near the hole at the opposite end of the dielectric block. Celui-ci est entierement cuivre ou argente a l'exception des parties a proximite de chaque trou et des electrodes d'entree et de sortie. This is entirely copper or silver except for the parts near each hole and input and output electrodes. Chaque trou plaque constitue essentiellement un resonateur coaxial. Each plated hole essentially a coaxial resonator. Le couplage entre des resonateurs coaxiaux adjacents obtenu a l'aide des trous plaques peut etre regle grâce a des fentes (110-114) ou a des trous supplementaires disposes entre les elements. The coupling between adjacent coaxial resonators obtained using plated holes can be adjusted by means of slots (110-114) or additional holes disposed between the elements. Deux ou plusieurs filtres ceramiques passe-bande uniques peuvent etre couples pour obtenir un filtre presentant une selectivite superieure ou un filtre multi-bande pour combiner et/ou trier selon la frequence deux ou plusieurs signaux en un signal composite ou a partir de celui-ci. Two or more single bandpass ceramic filters can be coupled to obtain a filter having higher selectivity or a multi-band filter for combining and / or sorting by frequency two or more signals into a composite signal or from the latter .

Method and apparatus for assigning duplex radio channels and scanning duplex radio channels assigned to mobile and portable radiotelephones in a cellular radiotelephone communications system

Abstract: A unique method and apparatus for efficiently assigning duplex radio channels and scanning duplex radio channels assigned to mobile and portable radiotelephones in a cellular communications system (Fig 1) Each cell (10, 20, 30) includes a base station radio (111, 121, 131) having a signalling channel and a plurality of voice channels, and a base site controller (112, 122, 132) adapted to utilize the methods embodying the present invention for controlling communications paths to mobile and portable radiotelephones The base station radios (Fig 2) include a signalling transceiver (250) operable on the signalling channel, a plurality of voice transceivers (220, 230) each operable on a voice channel, and a scanning receiver (240) for sampling the signal strength of active radiotelephones Transmitters of the signalling transceivers (250) and voice transceivers (220, 230) are combined (210) and coupled to an omnidirectional antenna (212); and the receivers of the signalling transceiver (250), voice transceivers (220, 230) and scanning receiver (240) are coupable to one or more of six sector antennas (214) In practicing the methods of the present invention, the microprocessor (358) controlled base site controller maintains high quality communications paths to mobile and portable radiotelephones by periodically monitoring their signal strength and when signal strength degradations are detected, either changing the base station sector antennas (214) coupled to voice transceivers (220, 230), increasing or decreasing radiotelephone power output, or handing radiotelephones off to another cell

Wide area coverage radio communication system and method

Abstract: A wide area coverage radio communication system of the type adapted to relay a message substantially simultaneously from a plurality of fixed location sites to a plurality of portable or mobile units includes a plurality of repeaters at each of the sites. Each of the repeaters is arranged to transmit and receive on a respective different frequency duplex pair or channel. Control means at one of the sites senses channel availability at all of the sites and causes one repeater at each of the sites to transmit the message on its respective different frequency. Access to the system by the portable units is provided on a trunked basis through the control means.

Maximum power tracker

Abstract: A buck regulator or impedance converter is disclosed for operating a current limited power supply such as a photovoltaic array at or near its maximum power point. The maximum power point for such a supply is achieved at the compliance voltage which is an almost constant voltage. Means are provided for sensing the voltage at the input of the regulator and for using this sensed voltage to control a logic circuit which, in turn, controls the duty cycle of a switching transistor. The output from the switching transistor is coupled to an LC filter and from there to the load. The logic circuitry, responsive to the sensed voltage, controls the duty cycle of the switching transistor in such a manner as to maintain the input voltage approximately constant and thus to maintain the power supply at or near its peak power operating point.

Multiple frequency message system

Abstract: In the preferred embodiment the multiple frequency receiver comprises a decoder responsive to a transmitted coded message signal having a special code for designating that the message is being sent on the local frequency and which is also responsive to the absence of the special code which indicates that the signals are being transmitted on a designated nationwide frequency. The decoder includes a microprocessor which generates an output to turn on the local frequency channel element so that the pager may receive the local frequency when the special code is detected and generates a second output to turn-on a nationwide frequency channel element so that the receiver can receive a nationwide frequency when the special code is absent. This enables the pager user to transfer from his local city to another city without having to manually adjust the pager.

Method and apparatus for dynamically selecting transmitters for communications between a primary station and remote stations of a data communications system

Abstract: A data communications system (Figure 1) that covers a geographic area divided into a plurality of non-overlapping zone (Figure 2) and includes a general communications controller (GCC, 104), a plurality of channel communications modules (CCM 106, 108, 110, 112) and associated transmitters (114, 120, 124) and receivers (116, 118, 122, 126, 128), and a plurality of portable radios (130, 132, 134). Message signals carrying alphanumeric information are communication between the GCC (104) and the portable radios (130, 132, 134) by way of a radio channel. Each CCM (106, 108, 110, 112) takes a signal strength measurement every time it receives a message signal from a portable radio (130, 132 or 134). The GCC (104) gathers the signal strength measurements from the CCM receivers (116, 118, 122, 126, 128) receiving the same message signal and computes an adjusted signal strength for each zone. The GCC (104) then selects the zone having the largest adjusted signal strength for determining the location of the portable radio (130, 132 or 134) that transmitted the message signal. Whenever the GCC (104) transmits a message signal to a portable radio, the CCM transmitter (114, 120, 124) is used that covers the zone having the largest adjusted signal strength for the last transmission from that portable radio (130, 132, 134). Since the GCC (104) can be simultaneously transmitting message signals to portable radios (130, 132, 134) in other zones using non-interfering CCM transmitters (114, 120, 124), information throughput is greatly enhanced.

Video graphic dynamic RAM

Abstract: A memory chip containing a standard dynamic RAM having the capability to serially read out data at a high rate of speed while performing standard RAM operations is provided. A standard memory latches a complete row of data into a latch. The data from the latch is then transferred upon command to a second latch or shift register where it is shifted out independently of the operation of the RAM.

Metallization and bonding means and method for VLSI packages

Abstract: An improved VLSI device package and an improved method for contacting VLSI devices, in which the occurrences of wire bond shorts and lead voltage drops are substantially reduced, are obtained by providing multiple lead levels in the package, with the N 2 leads on the upper lead level grouped into N 3 bunches separated by N 4 spaces, where each of the N 4 spaces aligns with a bonding target on a corresponding one of the N 1 leads on the lower level leads of the package, and where N 1

Double-sided flexible electronic circuit module

Abstract: A double-sided flexible electronic circuit module is provided having a flexible printed circuit board. The flexible circuit board has a plurality of conductive paths on each surface and a plurality of conductively plated-through apertures being connected to the conductive paths. One side of the flexible circuit board is adapted to carry components with leads; the other side of the flexible circuit board is adapted to receive components without leads. A carrier member, larger than the flexible circuit board and of a size and shape sufficient to accommodate the placement of at least one flexible circuit board, is also provided. The carrier member has a plurality of apertures which are in alignment with the apertures of the flexible circuit board, and a plurality of elongated slots in predetermined positions which extend the entire width of the flexible circuit board which is temporarily affixed onto the carrier member. All of the components are soldered to the flexible circuit board, the carrier member acting as a support member to the components having leads.

Surface denuding of silicon wafer

Abstract: A process is disclosed for preparing silicon wafers having a high quality, high lifetime surface layer and a bulk region characterized by a low lifetime and by a high density of precipitated oxygen gettering sites. A wafer having a relatively high concentration of interstitial oxygen is heated in a reducing ambient at a sufficiently high temperature and a sufficiently long time to cause a surface layer to be denuded of oxygen related defects and dislocations. The temperature is then ramped down to a lower temperature and the wafer is maintained at this lower temperature for a sufficient time to allow precipitation of oxygen within the bulk of the wafer.

Data signalling system.

Abstract: A data signalling system for transmitting signals between at least one primary station and a plurality of secondary stations. The system is well adapted for use in multiple unit radio communications systems capable of noise and data communications. A register model is utilized which permits a highly flexible signalling system compatable with a wide range of communications networks. Data transfer is accomplished using fixed length data packets which are error correction encoded and transmitted utilizing PSK modulation.

Variable color electrooptic display

Abstract: An electrooptic color display for displaying selectable indicia includes a ferroelectric ceramic element, such as a PLZT material, first and second polarizers on each side of the element, and a mechanism for selectively inducing a transverse electric field at selectable areas on the element, said areas corresponding to the indicia. The electric field can be produced by applying a voltage to transparent interleaved electrodes on one or both surfaces of the ceramic element. These areas produce spectrally selective phase retardation which causes the color of the indicia to be different from that of the background color. Preferably a separate retardation element which may be fixed, variable, or a combination of both, is disposed between the polarizers to provide a fixed color bias that determines the background color. This invention contemplates transmissive, reflective, and transflective color displays.

Series current limiter

Abstract: Field effect transistors are used in a series current limiter circuit. The field effect transistors are depletion type transistors and are interconnected in a manner to decrease conduction when an overvoltage or overcurrent condition is sensed. Biasing resistors are used to maintain the transistors in a non-conductive state until the overvoltage or overcurrent condition is removed.

Selective call paging and priority signalling system.

Abstract: A general purpose data control and information system (30-64) particularly well adapted for multiple unit (60-64) radio communications providing reliable enhancement to normal voice systems. The system provides addressing capability (Fig. 2, bits 0-15) along with data transfer (Fig. 3) and utilizes handshake and retransmission protocol to enhance flexibility and reliability. The system utilizes fixed length signalling packets, (Fig. 2), with error correction encoding, to permit data transfer, transmitter identification and control and status monitoring.

Data processor which can repeat the execution of instruction loops with minimal instruction fetches

Abstract: A pipelined data processor capable of automatically storing in an external memory all essential information relating to the internal state thereof upon the detection of an access fault during instruction execution. Upon correction of the cause of the fault, the data processor automatically retrieves the stored state information and restores the state thereof in accordance with the retrieved state information. The data processor then resumes execution of the instruction. The faulted access may be selectively rerun upon the resumption of instruction execution. In response to detecting a particular sequence of a loopable instruction followed by a conditional branch instruction which selectively branches back to the loopable instruction, the data processor enters a loop mode wherein the loopable instruction and the branch instruction are internally recirculated around the pipeline to save instruction fetch cycles.

Homotropic antenna system for portable radio

Abstract: An adaptable homotropic antenna system for use with a portable communication transceiver is described. The antenna system can be used for reception or transmission and can be completely enclosed within the portable transceiver housing. The homotropic antenna system evaluates the quality of a received signal and if the signal is below a predetermined threshold level, an alternate antenna will be selected. The antenna system will continue to sample the available antennas until an antenna produces a signal of acceptable quality.

Virtual machine data processor

Abstract: A data processor capable of automatically storing in an external memory all essential information relating to the internal state thereof upon the detection of an access fault during instruction execution. Upon correction of the cause of the fault, the data processor automatically retrieves the stored state information and restores the state thereof in accordance with the retrieved state information. The data processor then resumes execution of the instruction. The faulted access may be selectively rerun upon the resumption of instruction execution. Means are provided to verify that the retrieved state information is valid.

Electrical load monitoring system and method

Abstract: A microcomputer controlled monitoring system and method for detecting an electrical open, shorted or operative condition of an electrical load. A load switch circuit couples the load to a common voltage line and is controlled by a single drive line from a microcomputer controlled load monitor circuit.

Digital voice storage system

Abstract: A digital voice storage system adapted for use in a multiple unit land mobile radio communications system. The system utilizes a PSK signalling system with fixed length data packets to control a system capable of multiple message storage of speech at mobile stations. Up to eight 64K dynamic RAMS are used in conjunction with a microprocessor to store up to 42 seconds of speech comprising up to eight separate messages. In addition, the system permits base interrogation of mobiles to determine if a message has been stored for review by the base operator and to determine the remaining recording capacity and total recording capacity of the mobile.

Semaphore for memory shared by two asynchronous microcomputers

Abstract: An improved semaphore is described that arbitrates the access of a memory shared by first and second microcomputers operating asynchronously at the same speed or at different speeds. The semaphore includes a semaphore flip-flop producing a binary semaphore signal indicating whether or not the semaphore is owned, and an ownership flip-flop producing a binary ownership signal indicating which of the first or second microcomputers previously owned the semaphore. First gating circuitry decodes control signals from the first microcomputer and generates a read or write pulse signal. The read pulse signal from the first gating circuitry loads the semaphore signal and ownership signal into first and second flip-flops, respectively, whose outputs are applied to the data bus of the first microcomputer. Second gating circuitry decodes control signals from the second microcomputer and generates a read or write pulse signal. The read pulse signal from the second gating circuitry loads the semaphore signal and ownership signal into third and fourth flip-flops, respectively, whose outputs are applied to the data bus of the second microcomputer. If the first and second microcomputers access the semaphore simultaneously, access is granted to the second microcomputer since the output of the third flip-flop resets the first flip-flop to deny access to the first microcomputer.

Method and apparatus for coding messages communicated between a primary station and remote stations of a data communications system

Abstract: A data communications system is described in which variable length messages are communicated between a general communications controller (GCC) and a plurality of portable and mobile radios. The variable length messages include a bit synchronization field, a message synchronization field and a plurality of channel data blocks for efficiently and reliably handling long strings of data or text. Each channel data block includes an information field, a parity field for error-connecting the information field and a channel state field indicating whether or not the radio channel is busy or free. The GCC is coupled to a cellular arrangement of channel communications modules (CCM's), which each include a radio transmitter and/or radio receiver. The mobile and portable radios communicate with the GCC by way of the CCM's.

Socket and flexible PC board assembly and method for making

Abstract: The integral interconnect socket and flexible board assembly accepts an electronic module having a plurality of leads arranged in a predetermined pattern. The assembly includes a flexible printed circuit (PC) board having a plurality of conductors and a first set of holes disposed to respectively intersect the conductors. A substantially rigid platform is mounted to the PC board and has a second set of holes. The first and second set of holes are in alignment and define common apertures arranged in the predetermined pattern to receive the leads of the modules. A layer of metal plating formed within the apertures makes electrical connections with the respective conductors. Jacks are mounted to each aperture for receiving the leads and making electrical connections between the leads and the conductors.

QAM modulator circuit

Abstract: A method and means for quadrature amplitude modulation is described. The improved QAM modulator circuit utilizes a small read only memory to hold multiple versions of a signal constellation resulting in the elimination of hardware modulator circuits. In addition, the described device can be potentially any modulation scheme on an input signal which is sampled in time by modifying the contents of said ROM.

Communications system enabling radio link access for non-trunked radio units to a multifrequency trunked two-way communications systems

Abstract: An improved multifrequency trunked, two-way communications system is provided in which a plurality of conventional single channel radio units are provided access. The system includes a predetermined number of information channels that are shared by a plurality of trunked stations. A trunked controller assigns one of the information channels to a requesting trunked mobile unit. The requesting trunked mobile unit is enabled to operate on the assigned channel in response thereto. The improved communications system includes a radio access link which enables the single channel radio units to operate on an assigned information channel in the same manner as the trunked remote stations. The radio access link provides the plurality of conventional remote stations automatic access to the trunked system without requiring any modification of the conventional remote stations, and likewise without modification of the trunked remote stations and trunked controller.

Trichlorosilane production process

Abstract: A process for producing trichlorosilane and equipment for practicing that process are disclosed. The process is a two stage process which combines the reaction of silicon tetrachloride and hydrogen with silicon with the reaction of hydrogen chloride with silicon. In one embodiment of the invention a two stage reactor is provided with a first stage heated to a temperature of about 500°-700° C. and a second stage maintained at a temperature of about 300°-350° C. Each of the first and second stages of the reactor are charged with silicon particles. A mixture comprising hydrogen and silicon tetrachloride are flowed through the silicon particles in the heated first stage to cause a partial hydrogenation of the silicon tetrachloride. The effluent from the first stage includes trichlorosilane and unreacted hydrogen and silicon tetrachloride. Hydrogen chloride is added to this effluent and the mixture of gases are passed through the silicon particles in the second stage of the reactor.

Axial air gap brushless alternator

Abstract: A brushless alternator is disclosed having a stationary field coil and core surrounded by a stationary stator coil and core with a cylindrical air gap being defined therebetween A rotor assembly is fixed to a rotatable shaft and has interweaved separate magnetic finger assemblies joined together by a non-magnetic ring wherein these fingers are rotated in the cylindrical gap The stator and field cores are radially disposed with respect to the rotatable shaft The field core axially extends beyond the effective axial length of the field coil and provides at an axial position beyond the effective axial length of the field coil, at least one low reluctance axial flux gap between the field core and the magnetic fingers This flux gap conducts a substantial portion of the flux created by the field coil The field core also serves as a shaft bearing retainer and has a bearing grease reservoir comprising a cylindrical recess adjacent the shaft bearing

Processor for simulating digital structures

Abstract: A hardware simulator for simulating digital structures includes a general purpose computer and an improved simulator processor. The improved processor handles an advanced primitive having four inputs and one output and which is capable of representing a memory cell or similar structure. The architecture of the processor provides highly efficient compilation of the input states of a primitive and the primitive evaluator and resolver logic provide the output state in a minimum number of clock cycles. The simulator is a single, low cost unit capable of simulating 64K cell structures with a speed comparable to prior art simulators.