摘要:
In a wireless telecommunication network, hybrid (GPS and AFLT) mobile stations provide redundant position information, which is used for time base calibration and/or correction of position measurements. Every mobile station (i.e., handset or cellular phone) can be used as a test instrument, and data from regular wireless phone calls can be supplemented by data from drive-around field test units. The time base and/or position offsets are stored in a base station almanac data base along with other information used for obtaining the most reliable position fixes under a variety of conditions. An automatic system is provided for creating, updating, and maintaining the base station almanac data base. The automatic system not only characterizes the performance of the wireless network but also characterizes the performance of the position determination system. The automatic system provides performance feedback to system operators and customers.
摘要:
Techniques to implement MBMS services in a wireless communication system. In one aspect, a method is provided for processing data for transmission to a plurality of terminals. Frames of information bits (which may have variable rates) are provided to a buffer implementing a matrix. The matrix is padded with padding bits based on a particular padding scheme to support variable frame rates. The frames are then coded based on a particular block code to provide parity bits. The frame of information bits and the parity bits are then transmitted to the terminals. In another aspect, a method is provided for controlling the transmit power of a data transmission to a plurality of terminals. In accordance with the method, TPC streams are received from the terminals and processed to obtain a stream of joint power control commands used to adjust the transmit power of the data transmission.
摘要:
Techniques to implement MBMS services in a wireless communication system. In one aspect, a method is provided for processing data for transmission to a plurality of terminals. Frames of information bits (which may have variable rates) are provided to a buffer implementing a matrix. The matrix is padded with padding bits based on a particular padding scheme to support variable frame rates. The frames are then coded based on a particular block code to provide parity bits. The frame of information bits and the parity bits are then transmitted to the terminals. In another aspect, a method is provided for controlling the transmit power of a data transmission to a plurality of terminals. In accordance with the method, TPC streams are received from the terminals and processed to obtain a stream of joint power control commands used to adjust the transmit power of the data transmission.
摘要:
Techniques to time-share a common channelization code among multiple terminals for compressed mode transmissions. Each terminal is initially assigned a respective channelization code used to channelize data transmitted in non-compressed frames for the terminal. A common channelization code used to channelize data transmitted in compressed frames for the terminals is also selected. Each compressed frame includes one or more compressed transmissions and all or a portion of a transmission gap. The compressed frames for the terminals are scheduled such that the compressed transmissions for the compressed frames do not overlap. Thereafter, non-compressed frames for each terminal are channelized with the channelization code assigned to the terminal, and compressed frames for the terminals are channelized with the common channelization code. The compressed frames may be scheduled to be (1) non-overlapping at their frame boundaries, (2) non-overlaping with respect to the compressed transmissions, and/or (3) interlaced.
摘要:
Techniques to time-share a common channelization code among multiple terminals for compressed mode transmissions. Each terminal is initially assigned a respective channelization code used to channelize data transmitted in non-compressed frames for the terminal. A common channelization code used to channelize data transmitted in compressed frames for the terminals is also selected. Each compressed frame includes one or more compressed transmissions and all or a portion of a transmission gap. The compressed frames for the terminals are scheduled such that the compressed transmissions for the compressed frames do not overlap. Thereafter, non-compressed frames for each terminal are channelized with the channelization code assigned to the terminal, and compressed frames for the terminals are channelized with the common channelization code. The compressed frames may be scheduled to be (1) non-overlapping at their frame boundaries, (2) non-overlaping with respect to the compressed transmissions, and/or (3) interlaced.
摘要:
Techniques for providing an improved position estimate for a device in instances of relatively large dilution of precision. In a method, position estimates for a number of transmitters (e.g., GPS satellites and/or base stations) and a set of initial measurements (e.g., pseudo-ranges) are initially received. An Update Vector for a current device position estimate is computed. Non-convergence of the current device position estimate toward a target position estimate is detected and, if true, the Update Vector is adjusted (e.g., reduced in magnitude by a scaling factor) to increase the likelihood of convergence to the target position estimate. The current device position estimate is then updated based on the (possibly adjusted) Update Vector. Non-convergence may be detected based on the number of iterations performed without reaching the target position estimate and/or phase reversal in two consecutive Update Vectors. The scaling factor may be increased with each detected event indicative of non-convergence.