Abstract:
A method of system access from a wireless device to a wireless network, the network having a plurality of base stations includes the steps of: selecting at least one reverse link cost metric from a list of predetermined reverse link cost metrics; determining a reverse link cost according to the selected at least one reverse link cost metric; selecting a candidate base station from the plurality of base stations; sending a probe signal at the reverse link cost to the candidate base station; waiting for a response from the candidate base station within a timeout period; and repeating steps until timeout, or until the condition that a response is received from at least one candidate base station so that at least one candidate base station can be used to provide system access from the wireless device to the wireless network.
Abstract:
The present invention is a photoconductive element that includes an electrically conductive support, an electrical barrier layer disposed over said electrically conductive support, and disposed over said barrier layer, a charge generation layer capable of generating positive charge carriers when exposed to actinic radiation. The barrier layer includes a vinyl polymer with aromatic tetracarbonylbisimide side groups and crosslinking sites.
Abstract:
Methods and apparatus for expeditiously releasing network resources for a mobile station based on low battery and lost signal conditions are disclosed. The wireless network (104) receives a power down warning message from the mobile station (102) indicative of a low battery condition. The wireless network (104) then identifies whether a lost signal condition exists with the mobile station (102). In response to receiving the power down warning message and subsequently identifying the lost signal condition, the wireless network (104) causes network resources for the mobile station to be released. The wireless network (104) infers that the mobile station (102) has powered down due to low battery without enough time to send a power down registration to the wireless network (104).
Abstract:
The application relates to wireless networks and more particularly to a method of reducing factory test time of receiver sensitivity in a Code Division Multiple Access (CDMA) wireless device. Under TIA/EIA/-98E, the radio frequency (RF) sensitivity of a CDMA wireless receiver is the minimum received power, measured at the mobile station antenna connector, at which the frame error rate (FER) does not exceed 0.5% with 95% confidence. In order to reduce the test time of FER test method, the relation between correlated energy (or Ec/Io) and FER is determined using simulated traffic and the correlated energy (or Ec/Io) measurement is then used as the test parameter on like models to achieve the same or superior test confidence with significantly reduced test time.
Abstract:
A method and apparatus for creating a communication group using an electronic address book to facilitate Push-to-Talk over Cellular (PoC) group communication sessions are disclosed. A group definition for determining members of the new PoC Group is composed from one or more contacts from the electronic address book such as by selecting from the address book using the mobile station. The group definition may include logical operators to define the combination of contacts. A name may be specified for the new group. The assembly of the PoC Group list of members may be performed by the mobile station, a communication network server for maintaining PoC Groups (e.g. a Group and List Management Server (GLMS)) or an email server.
Abstract:
Methods and apparatus for facilitating concurrent Push-to-talk over Cellular (PoC) group communication sessions for a mobile station (102) are disclosed. A first PoC communication session (550) for a first user group (504) is maintained while a second PoC communication session (552) for a second user group (506) is concurrently maintained, where the second user group (506) has at least one common member (516) with the first user group (504). The second user group (506) may have at least one member (518, 520) which is not included in the first user group (504). Through a user interface, a PoC user may select between the first and the second user groups (504 and 506) for communication or combine the communications. In an alternative embodiment, all of the members (518, 520, 522) of a second user group (604) may be included in a first user group (602). In a specific approach, encrypted data packets of a PoC communication sub-session are communicated during a PoC communication session. If a key for the encrypted data packets is known for the mobile station (102), the encrypted data packets are decrypted to facilitate the PoC communication sub-session involving the mobile station (102); otherwise the encrypted data packets are discarded.
Abstract:
It has now been found that in some transmitter implementations which transmit multiple code channels, for example CDMA transmitters, the observed power for each code channel at the output relative to the other code channels is dependent upon the total transmit power due to non-linearities in the transmitter. Methods and apparatus are provided which use pre-set digital gains or digital gain adjustments to compensate for the non-linearities as a function of total transmit power such that at the output, the desired relative powers are observed.
Abstract:
Methods and apparatus for limiting communication capabilities in mobile communication devices are disclosed. In one illustrative example, a predetermined condition such as an unsatisfactory temperature or a low battery voltage is detected at the mobile communication device. At this time, a communication request for communicating information through a wireless communication network is received through a user interface. If the communication request is for a non-emergency communication, the non-emergency communication is inhibited during the existence of the predetermined condition. If the communication request is for an emergency communication, however, the emergency communication is allowed despite the existence of the predetermined condition. The emergency communication may be allowed at a reduced transmit power and/or using limited coding/modulation methods. The emergency communication may be a “911” voice call or an emergency message. The reception of communications may still be allowed but inhibited upon more adverse conditions.
Abstract:
In many applications such as automobiles on busy highways, if a lot of vehicles on road are equipped with Doppler radars to help improve driving safety, no matter human-driven or auto-driven, if the radars use same frequency band, avoiding interference between them is a hard task. Assigning distinct frequencies is one of the solutions, however not only it wastes expensive spectrum resource, but also the task itself to dynamically assign frequency to vehicles randomly come together becomes a hard one to do. The disclosed invention of Doppler group radar will allow radar devices to work together using shared frequency band without interfering one another, without sacrificing performance, and without much increase in costs.
Abstract:
The present invention discloses a 3D polarization beam splitter based on 2D photonic crystal slabs which comprises a 2D photonic crystal slab positioned at the top part, a 2D photonic crystal slab positioned at the bottom part and perpendicular to the top 2D photonic crystal slab, and an input coupling dielectric block; a P polarization wave output waveguide is positioned in the top 2D photonic crystal slab; an S polarization wave output waveguide is positioned in the bottom 2D photonic crystal slab; the output port of the P polarization wave output waveguide and the output port of the S polarization wave output waveguide are apart from each other in 3D space; the photonic crystal slabs include a background dielectric material and dielectric rods. The structure of the present invention has a small volume, high degree of polarization, high light transmission efficiency; it is convenient for optical integration and highly efficient; it is suitable for large-scale optical integrated circuits; and it can realize the polarization beam splitting function for different wavelengths.