Showing papers by "Motorola Solutions published in 2001"

Method and apparatus for providing ip mobility for mobile networks

Abstract: IP mobility solution for mobile network(s) combines features of IP multicast and mobile IPv6. The mobile network defines a mobile router (106) attached to one or more mobile network hosts (102). Upon movement of this network from a home network to a foreign network, the router obtains a multicast care of address for the attached network hosts, creating a binding between the mobile subnet prefix and the multicast care of address. The router communicates the binding information to a home agent (150). A correspondent node sends packets to a mobile network nodes home address. They are intercepted by the home agent and tunneled to the router via the multicast care of address. The router receives the packet and forwards it to the targeted mobile network node. Optionally, the router may send a binding update to the correspondent node, therefore, future packets travel the shortest tree, avoiding the overhead of tunneling.

A protocol for a self-organizing network using a logical spanning tree backbone

Abstract: A network protocol for low-cost, low-power device coupled to a self-organizing wireless network using a spanning tree backbone architecture is described. In this protocol, physical and logical network construction and maintenance operations, which supports efficient data routing in the network, are performed. The construction phase (991) in conjunction with the maintenance phase (905) insures the self-organizing capability of the network. At the same time, the maintenance (905) operations provide a self-healing mechanism (920) so that the network can recover from node failures and a self-updating mechanism so that the network can expand as more nodes enter the system. Also, the logical backbone hierarchy will facilitate multi-hop communication. The construction of a logical layered spanning tree backbone architecture from an underlying physical topology allows seamless data communication routing between all nodes in the network.

Communication network with a collection gateway and method for providing surveillance services

Abstract: A communication network (10) utilized for providing communications between a first party and a second party includes a surveillance server (26) within a core network (10) to provide communication surveillance capability. The core network (10) may be a packet data network, and the surveillance server (26) is operable responsive to trigger information to establish communications surveillance. Communication surveillance may be established by creating duplicate bearer packets of those data packets carrying the communicated data between the parties, creating duplicate control packets of those data packets carrying in-band or out-of-band call control information between the parties and within the packet data network, and/or various combinations thereof. The duplicate bearer packets and the duplicate control packets are routed to appropriate authorized law enforcement agencies for providing surveillance.

Method of wireless communication in restricted wireless zones

Abstract: A method of wireless communication in restricted wireless zones ( 102 ) includes providing a restricted wireless zone communication system ( 104 ) having one or more wireless nodes ( 106 ) and a wireless device ( 110 ) having a first transceiver ( 150 ) restricted from operating in a restricted wireless zone ( 102 ) and a second transceiver ( 152 ) not restricted from operating in a restricted wireless zone ( 102 ). Upon entering restricted wireless zone ( 102 ) first transceiver ( 150 ) is disabled and second transceiver ( 152 ) is enabled to communicate with restricted wireless zone communication system ( 104 ). Wireless device ( 110 ) is then able to send and receive content from outside restricted wireless zone ( 102 ). Upon wireless device ( 110 ) leaving restricted wireless zone ( 102 ), the second transceiver is disabled and the first transceiver ( 150 ) is enabled.

Data transmission and reception method and apparatus

Abstract: A datastream of bits (which may itself be comprised of a plurality of datastreams as derived from a plurality of sources) are coded (21) and then interleaved (12) across a plurality of transmitters (25 and 26) and a plurality of subcarriers (27) as supported and shared by the transmitters. If desired, the bits can be mapped to corresponding symbols prior to transmission. The resultant information is transmitted simultaneously by the transmitters using the shared channel of subcarriers. Upon reception, the received signals are de-interleaved and decoded to recover the original datastream for each sources.

Slot format and acknowledgement method for a wireless communication system

Abstract: A slot format and acknowledgment method for use in a communication network that contains one or more wireless links. The slot format provides for the segmenting and reassembly of packets for transport over a wireless link. It also provides support for multiple types of service for the data being carried over the wireless link as well as allocating of access to the wireless link among a plurality of communication units. The acknowledgment method provides for detection of errors over the wireless link, the selective acknowledgment of error-free transmissions and the selective resending of transmissions received in error.

Dense mode IP multicast call scoping in a wireless communication system

Abstract: Methods are disclosed for limiting the scope of flooding of dense mode IP multicast calls. A multicast scope value (e.g., TTL scope or hop limit) is determined for each call based on the locations of participating devices for the call at one or more destination sites, zones or zone clusters. The multicast scope value is adjusted based on user location, as wireless users may roam from site to site or zone to zone (or zone cluster). When a user sources packets for a call, the packets include the multicast scope value. The packets are transported, according to dense mode routing protocols, across various router interfaces of a packet network. The router interfaces are assigned various thresholds based on their location in the network. Packets are not flooded across router interface(s) having thresholds that exceed the packet's multicast scope value. Thus, through judicious choice of multicast scope value, the flooding of packets for a call may be constrained to within a single zone (or zone cluster), or allowed to proceed to remote zones.

Amplifier predistortion system and method

Abstract: An adaptive predistortion linearization system includes input path digital-to-analog converters (DACs), error path DACs, a digital signal processor, and a radio frequency (RF) combiner. The digital signal processor includes a look-up table storing complex gain coefficient values. The digital signal processor generates an error signal based on the complex input signal and the complex gain coefficients by using a vector decomposition calculation. Feedback from a power amplifier can be provided to a training algorithm for periodically updating the gain coefficient values stored in the look-up table. By performing separate D/A conversions, the error path and input signals can be separately filtered. This separation also permits the error signal to be decoupled from the complex input signal, which facilitates an improvement in the wide-frequency-offset noise performance of the system.

Method of communication in a radio frequency identification system

Abstract: A first request is transmitted to activate a set of tags in a first state. A first set of data symbols is received. In response to receiving the first set of data symbols, a first acknowledgement symbol transmitted. An acknowledgement symbol is transmitted in response to each subsequent set of data symbols received. A second request is transmitted to activate a second set of tags in a second state when a set of data symbols is not received within a predetermined time, wherein the first state is different from the second state.

Modulated radio frequency signal generation method and modulated signal source

Abstract: A modulated signal source for implementing A modulated signal method of a generating a modulated signal having a radio frequency based upon a linear mixing of signals is disclosed. An in-phase pulse signal modulator of the modulated signal source provides an in-phase pulse modulated signal in response to a reception of a baseband in-phase signal and an in-phase clock signal with the in-phase clock signal and the in-phase pulse modulated signal being synchronized. A quadrature pulse signal modulator of the modulated signal source provides a quadrature pulse modulated signal in response to a reception of a baseband quadrature signal and a quadrature clock signal with the quadrature clock signal and the quadrature pulse modulated signal being synchronized. A switch signal generator of the modulated signal source generates an in-phase switch signal and a quadrature switch signal in response to a reception of the in-phase clock signal, the in-phase pulse modulated signal, the quadrature clock signal, and the quadrature pulse modulated signal. The in-phase clock signal and the in-phase switch signal are synchronized, and the quadrature clock signal and the quadrature switch signal are synchronized. A radio frequency signal generator of the modulated signal source provides one or more modulated signals having a radio frequency in response to either a reception the in-phase switch signal and the quadrature phase signal, or a reception of a switch signal as a function of the in-phase switch signal and the quadrature phase signal.

Method and apparatus for organizing and scheduling multimedia data transfers over a wireless channel

Abstract: A radio frequency communications system ( 100 ) includes wireless terminals ( 102 ) and base sites ( 104 ). The wireless terminals communicate with the base sites over a radio frequency channel ( 106 ). The base sites are interconnected to each other and other network elements via a packet network. The communication system has a radio frequency channel ( 400 ) with time slots ( 406, 408 ) for transmission of both delay-sensitive data, such as streaming audio and video, and non-delay-sensitive data. A method and apparatus are provided for determining whether a time slot in the radio frequency channel is to be allocated to delay-sensitive data or non-delay-sensitive data ( 704, 706, 708 ). Each packet of data transmitted over the wireless channel has a type of service field ( 900 ). The type of service field has a precedence or priority value ( 902 ) and a service type ( 904 ). The priority values are used to determine which packet should be transmitted across the radio frequency channel next and the service type determines the transmission protocol.

Vacuum microelectronic device and method

Abstract: A vacuum microelectronic device ( 10,40 ) emits electrons ( 37 ) from surfaces of nanotube emitters ( 17, 18 ). Extracting electrons from the surface of each nanotube emitter ( 17 ) results is a small voltage variation between each emitter utilized in the device ( 10, 40 ). Consequently, the vacuum microelectronic device ( 10,40 ) has a more controllable turn-on voltage and a consistent current density from each nanotube emitter ( 17,18 ).

Slot format and method for increasing random access opportunities in a wireless communication system

Abstract: A communication system and method for communicating information in one or more time slots a predetermined bandwidth is disclosed. The system and method comprise communicating information, by at least one communication unit, in selected one or more random access subslots. The one or more times slots are divided into multiple subchannels, wherein each subchannel of the multiple subchannels is non-overlapping in frequency and divided into the one or more random access subslots that is non-overlapping in time.

FED cathode structure using electrophoretic deposition and method of fabrication

Abstract: A method of fabricating a field emission device cathode using electrophoretic deposition of carbon nanotubes in which a separate step of depositing a binder material onto a substrate, is performed prior to carbon nanotube particle deposition. First, a binder layer is deposited on a substrate from a solution containing a binder material. The substrate having the binder material deposited thereon is then transferred into a carbon nanotube suspension bath allowing for coating of the carbon nanotube particles onto the substrate. Thermal processing of the coating transforms the binder layer properties which provides for the adhesion of the carbon nanotube particles to the binder material.

Method and apparatus for determining and reserving bandwidth for transmitting delay-sensitive streaming data over a radio frequency channel

Abstract: A radio frequency communications system ( 100 ) includes wireless terminals ( 102 ) and base sites ( 104 ). The wireless terminals communicate with the base sites over a radio frequency channel ( 106 ). The base sites are interconnected to each other and other network elements via a packet network. A method and apparatus determine for a particular delay-sensitive application on the wireless terminal, for example, an audio or video transmission, the requirements for bandwidth for transmission over the radio frequency channel ( 500, 502 ). After the requirements on the radio frequency channel are determined, the necessary channel bandwidth, if available, is reserved or allocated to guarantee performance to the application ( 510 ). The reserved bandwidth is utilized by selectively granting access to the radio frequency channel on the basis of the bandwidth allocated to the device.

Methods for reliably sending IP multicast packets to multiple endpoints of a local area network

Abstract: Methods are disclosed for determining a link Op from among a plurality of host devices on a LAN, for exchanging control messages between a communication server and one or more sites having a link Op and a listening Op and for the link Op and/or listening Op to detect and recover from missing packets in a sequence of IP packets received from the server. The link Op and listening Op join a control multicast group address to receive control messages from the server. The link Op establishes a reliable message transfer session with the server. Upon the link Op detecting a missing packet, the link Op may request that the communication server resend the packet. Upon the listening Op detecting a missing packet, the listening Op determines whether the link Op will request retransmission of the missing packet. If the link Op is determined to not request retransmission of the missing packet, the listening Op requests retransmission of the missing packet or accepts the packet as missing and processes an out-of-sequence packet. If the link Op is determined to request retransmission of the missing packet, the listening Op discards the packet and relies upon the link Op to request retransmission of the missing packet.

Method and apparatus for facilitating wireless communications with a nonautomotive roaming object

Abstract: A radio (10) communicates compatibly with a dedicated short range roadside information service and is adapted and configured to be worn by a pedestrian or otherwise mounted on or installed in a variety of nonautomotive roaming objects. Various modes of operation are supported including a beacon mode (50), a remote transmitter mode (60), a remote disable mode (70), and a location based operating mode (80).

Method for mapping poor coverage areas

Abstract: A method of creating a database of poor coverage areas (120) in a wireless communication system includes (100) determining if a signal quality metric (204) of a communication link (130) in a poor coverage area (120) is below a signal quality threshold (202) then incrementing a poor coverage area counter (210), if not, incrementing a good coverage area counter (212). Storing one or more previous coverage areas (138-140) traversed by wireless device (102) prior to entering the poor coverage area (120) and calculating a trajectory (136) to the poor coverage area (120) based on one or more previous coverage areas (138-140) and poor coverage area (120). Subsequently, anticipating entry of the wireless device (102) into the poor coverage area (120) utilizing the trajectory (136) to the poor coverage area (120) and alerting a user of wireless device (102).

Method of scrambling and descrambling data in a communication system

Abstract: A scrambling method (510) divides a set of data (200) into a first portion and a second portion. A first scrambling method is performed on the first portion of the set of data to create a scrambled first portion of the data. The second portion of the set of data is modified with the scrambled first portion of the set of data to create a modified second portion of the set of data. A second scrambling method is performed on the modified second portion of the set of data to create a scrambled second portion of the set of data. The scrambled first portion of the set of data is modified with the scrambled second portion of the set of data to create a scrambled set of data (220). A descrambling method (520) reverses the scrambling method (510) to create a descrambed set of data (200).

Method of dynamically configuring access to services

Abstract: A method of dynamically configuring access to services (114, 130) between a remote communications node (104) and a remote communications device (106) includes determining if the remote communications node (104) is communicating with a distributed communications system (100). The remote communications node (104) is configured as a primary gateway (301, 401) if the remote communications node (104) is communicating with the distributed communications system (100) and configured as a secondary gateway (303, 403) if it is not. A remote communications device (106) is initialized and the remote communications node (104) and remote communications device (106) are dynamically configured to optimally access services (114, 130) in a serial configuration.

Binding proxy for mobile devices in a data network

Abstract: Binding proxies are used to reduce packet routing delays and call setup delays in a data network made up of a plurality of subnetworks. The binding proxy detects when a mobile device connects to a subnetwork and sends a binding message to various correspondent device(s) in the data network. The binding message contains a care-of-address of the mobile device that allowing the correspondent device(s) to send messages directly to the subnetwork that the mobile device is connected, thereby bypassing a home agent of the mobile device.

Timing estimation method and apparatus for a location system

Abstract: A first signal and a second signal are detected. The first and second signals are transmitted according to a timing pattern. An arrival time is identified for the first and second signals. Based on the timing pattern and the estimated arrival times of the first and second signals, a set of parameters is derived that characterize a timing relationship between a first device (100) and a second device (200).

Methods for achieving reliable joins in a multicast IP network

Abstract: Methods are described that enable host devices (138, 140, 148-156) of a multicast IP network (100) to reliably join multicast group address(es) in talkgroup or point-to-point calls. For a talkgroup call, a sourcing host sends (206) 'hello' packets or payload to one or more network devices (108-114), addressed to a multicast group address. The receiving host issues a join command to the one or more network devices in an attempt (308) to reliably join the multicast group address. If any packets are received (312) by the receiving host within a designated time period associated with the attempt, the receiving host is reliably joined to the multicast group address. For a point-to-point call, a first and second host participating in the call receive (602) a pair of multicast group addresses, one designated for sourcing packets and the other designated for receiving packets. The designated 'source' and 'receive' multicast group address are complementary for the first and second hosts. When the first or second host is acting as a source, it sends hello packets (610) or payload (608) addressed to its designated 'source' multicast group address. When the first or second host is acting as a receiver, it attempts (614) to join its designated 'receive' multicast group address. The first or second host acting as a receiver knows that it is reliably joined to its designated 'receive' multicast group address if it receives (618) any packets addressed to that address within a designated time period.

Method and apparatus for incorporating pager functionality into a land mobile radio system

Abstract: A land mobile radio system receives paging messages communicated via a paging service communication protocol, decodes the paging messages to identify respective target recipients of the paging messages and determines whether the target recipients are members of a user group. If a target recipient is a member of the user group, a communication unit (e.g., radio or console) of the target recipient is identified, the message is converted to an appropriate protocol (e.g., a wireless protocol) and sent to the communication unit.

Vacuum microelectronic device

Abstract: A vacuum microelectronic device ( 10 ) is formed by applying a conditioning voltage or field between the anode ( 17 ) and the electron emitters ( 13 ). The conditioning field has a value sufficient to move some of the electron emitters ( 13 ) in a direction toward the conditioning field. Some of the electron emitters ( 13 ) remain in that position after removing the conditioning field.

Self-extracting re-configurable interface used in modular electronic architecture

Abstract: A re-configurable interface used in modular electronic architectures includes a host (203) and one or more modules (201) for interfacing with the host (203) to provide additional functionality. A configuration controller (209) located in the host (203) is for reading a memory device (215) located in the module (201) for providing configuration information to the host. The pin controller (209) then is able to reconfigure pins of the host connector (207) to communicate with the module (201).

Apparatus and method for downloading journey-related information

Abstract: Vehicles (106) are equipped with two-way communication units (401) that communicate with roadside (114) and vehicular mounted two-way communication units to receive and/or exchange journey-related information. When approaching a geographic zone that does not support such services, a given vehicle (106) can receive at least a partial download of journey-related information concerning the second geographic zone (102) while still proximal to the entry border (107) for that zone (102). The download can be implemented wirelessly, through hard physical contact, or both. The download may also be at least partially concluded while traveling within the second geographic zone (102) through use of a second non-compatible wireless service such as wireless telephony.

Ridged reflector for an optical display

Abstract: A ridged reflector (10) for use in an optical display (12) comprises a polymeric layer (70) having a ridged surface (32) and an opposite surface (34) opposite the ridged surface (32). The ridged surface (32) includes a series of ridges (36). Each of said ridges (36) has a first face (42) and a second face (44) intersecting the first face (42). The first face (42) is oriented at a first angle (56) relative to a plane parallel to the opposite surface (34). A reflective metallic layer (68) overlies at least the first faces (42) of the polymeric layer (70). The first angle (56) is adapted to reflect and biasedly focus light obliquely intercepting the first face (56) into a radiation pattern about a normal axis (38) extending orthogonally from the opposite surface (34). The first face (42) may be curved to tailor a shape of the radiation pattern.

Method and apparatus for digital frequency synthesis

Abstract: A digital frequency synthesizer includes one or more reference clocks (104, 1316, 1502A, 1504A, 1506A) optionally coupled through one or more pulse width reducers (106) to one or more main delay lines (108, 702, 1502B, 1504B, 1506B) that include a plurality of output taps (108B-108I, 702B-702E). During at least certain periods of the reference clock (104) a plurality of the output taps are coupled to a common output (130, 1312, 1508), thereby producing an output signal that has a frequency that exceeds a frequency of the one or more reference clocks. The coupling is preferably accomplished by transmission gates (114, 128, 720-724, 1420-1434) that are switched by gating pulses that are received from decoders (148, 150, 1418) via gating signal delay lines (134-146, 704-718, 1404-1416).

System and method of achieving dynamic channel bandwidth

Abstract: Fixed network equipment ( 100 ) initializes a channel aggregation strategy and establishes a default channel aggregation. A request for a service requiring additional bandwidth is received from a device. An updated channel aggregation is generated based upon the request and the channel aggregation strategy to create an updated channel aggregation. The updated channel aggregation is signaled to at least one mobile station ( 116 ) via an in-band message.