Abstract: Methods and systems for generating a variable spacing pulse position modulated (VSPPM) signal for transmission across an ultra-wideband communications channel. The variable pulse position modulated spread spectrum signal is created by encoding every M input data bits from an input data stream into a symbol consisting of Nc chips. Each chip is divided into 2M sub-chips and each sub-chip is further divided into Np time slots. A pulse is transmitted for each chip in the symbol. During each chip period, the pulse is placed in the sub-chip corresponding to the binary M-tuple (or symbol) value. A time hopping code sequence consisting of Nc elements with a one-to-one chip association is then applied to each symbol so that the position of each pulse is shifted to the appropriate time slot that corresponds to the time hopping code value.

Abstract: A neighbor list of potential hand-off base stations is varied to control call blocking and dropping rates. The list may be varied in accordance with real-time traffic flow criteria.

Abstract: Communication between devices participating in a teleconference or the like is maintained without the need for each device to separately obtain new domain access rights as one or more of the devices comes in contact with a new domain.

Abstract: The ability to maintain communications between wireless nodes (e.g., devices), moving substantially as a group, as the group moves from one domain to another is provided without the need for each member of the group to separately obtain domain access rights.

Abstract: A method of communication between a user station and first and second base stations in which the user station is simultaneously in bi-directional wireless communication with said first and second base sttions, including a data transmission step in which an uplink signal including user data for communication to another user via the base stations is transmitted from said user station to said first and second base stations, said base station data (23) in said uplink signal including first items (26) that are processed selectively in said first base station (1) and second items (27) that are processed selectively in said second base station.

Abstract: A method and apparatus for increasing the accuracy and reliability of geolocation estimates for wireless communication networks devices includes calculating a geolocation estimate of a wireless communication device for a plurality of time periods, and selecting from the plurality of calculated geolocation estimates, a most reliable geolocation estimate of the wireless communication device.

Abstract: A geo-location technique for use in mobile communications networks employs both FDD and Time Division Duplex (TDD) modes of operation, and is applicable when both FDD and TDD systems are jointly deployed or both FDD and TDD modes of a wireless system such as UMTS are jointly activated. It has been determined that the near-far interference can be much easier controlled on purpose in the TDD mode than in the FDD mode thanks to the slotted data transmission nature of a TDD system that permits adjustment of the interference level at the time slot level instead of the frame level. Indeed, in a TDD system, loading and interference levels can be gracefully decreased in a single time slot without harming the ongoing traffic or complicating the power control operations, as would be the situation in a UMTS FDD system via IPDL or similar solutions that require to mute the pilot transmission. The invention applies to both situations whether or not the terminals are equipped with a dual receiver.

Abstract: An adaptive pulse position modulated CDMA scheme for use in UWB communications systems is disclosed. A stream of input bits is encoded with spreading code sequence. The spreading code sequence consists of a number of code elements that may have one of two values. Each bit is encoded into a symbol consisting of a predefined number of chips, which are transmitted during a symbol period. Next, at least one code element is associated with each chip in the symbol. Then, an encoded pulse is generated in each chip. Each encoded pulse has a value determined by multiplying the data bit with the code value associated with the particular chip. The encoded pulse is then pulse position modulated by shifting the position of the pulse to a first position or a second position within the chip depending upon the encoded value of the pulse.

Abstract: Methods and systems for generating a variable spacing pulse position modulated (VSPPM) signal for transmission across an ultra-wideband communications channel. The variable pulse position modulated spread spectrum signal is created by encoding every M input data bits from an input data stream into a symbol consisting of Nc chips. Each chip is divided into 2M sub-chips and each sub-chip is further divided into Np time slots. A pulse is transmitted for each chip in the symbol. During each chip period, the pulse is placed in the sub-chip corresponding to the binary M-tuple (or symbol) value. A time hopping code sequence consisting of Nc elements with a one-to-one chip association is then applied to each symbol so that the position of each pulse is shifted to the appropriate time slot that corresponds to the time hopping code value.

Abstract: A wireless-global positioning system determines the location of a wireless mobile communication device from reliable position measurements and wireless network downlink measurements. The wireless network downlink measurements obtained are then used in conjunction with a database for pattern matching or contour matching. The difficulty of building and maintaining that database is alleviated by using those network downlink measurements associated with the reliable position measurements to populate the database, such as GPS measurements or those obtained through enhanced based positioning technique (EOTD). The increased database accuracy subsequently improves the quality of position location measurements from the wireless network.

Abstract: A cellular communications system permits handover of a group of mobile stations (15) having like characteristics from a base station (13) operating in one type of network e.g. UMTS to a base station (16) operating in a different type of network e.g. GSM, or from a first carrier frequency to a second carrier frequency both being supported by the same base station, thereby relieving congestion in an overloaded cell by handing over a group of calls to an under-loaded one. The invention has the benefits of enabling such a handover with the minimum of signalling overhead.

Abstract: A wireless-global positioning system determines the location of a wireless mobile communication device from reliable position measurements and wireless network downlink measurements. The wireless network downlink measurements obtained are then used in conjunction with a database for pattern matching or contour matching. The difficulty of building and maintaining that database is alleviated by using those network downlink measurements associated with the reliable position measurements to populate the database, such as GPS measurements or those obtained through enhanced based positioning technique (EOTD). The increased database accuracy subsequently improves the quality of position location measurements from the wireless network.