Abstract:
Techniques to increase capacity in a wireless communications system. In an aspect, systematic non-transmission, or "blanking," of minimal-rate frames transmitted in a communications system is provided. In an exemplary embodiment, eighth rate frames in a cdma2000 voice communications system are systematically substituted with null-rate frames carrying zero traffic bits. Provisions are nevertheless made for the transmission of certain designated as "critical" by, e.g., a vocoder. The receiver detects the presence of null rate or non-null rate transmissions and processes the received frames accordingly, including updating an outer loop power control only in response to non-null rate frames. Further techniques for changing the pilot transmission gating pattern to assist the receiver in detecting null rate frames are provided. In another aspect, early termination of a signal transmission over a wireless communications link is provided. In an exemplary embodiment, a base station (BS) transmits power control groups (PCG's) for a frame over a forward link (FL) to a mobile station (MS) until accurate reception of the frame is acknowledged by the MS over a reverse link (RL), possibly before all PCG's of the frame are received over the FL. Possible ACK signaling methods are defined for channels associated with a cdma2000 wireless communications system. In another exemplary embodiment, techniques for reverse link early termination are also provided.
Abstract:
Interference that occurs during wireless communication may be managed by determination and application of an adaptive path loss adjustment. A method, apparatus and medium of communication determine a level of excess received interference based at least in part on out-of-cell interference (Ioc). The path loss is adjusted by an additional path loss on an uplink signal when the level of excess received interference exceeds an interference target that would cause a Rise-over-Thermal (RoT) metric to exceed stable communication.
Abstract:
Transmit power (e.g., maximum transmit power) may be defined based on the maximum received signal strength allowed by a receiver and a minimum coupling loss from a transmitting node to a receiver. Transmit power may be defined for an access node (e.g., a femto node) such that a corresponding outage created in a cell (e.g., a macro cell) is limited while still providing an acceptable level of coverage for access terminals associated with the access node. An access node may autonomously adjust its transmit power based on channel measurement and a defined coverage hole to mitigate interference. Transmit power may be defined based on channel quality. Transmit power may be defined based on a signal-to-noise ratio at an access terminal. The transmit power of neighboring access nodes also may be controlled by inter-access node signaling.
Abstract:
Techniques to efficiently attempt acquisition of a packet data system (e.g., an IS-856 system). If a terminal has acquired one or more channels in a voice/data system (e.g., an IS-2000 system), then it can attempt acquisition on channels in the packet data system that are co-located with the acquired channels in the voice/data system. Multiple acquisition modes may be used, and on-going acquisition attempts on the co-located channels may be performed using one acquisition mode at a time in order to reduce power consumption. Acquisition attempts may be performed in a "ping-pong" manner to improve the likelihood of acquisition. For a ping-pong search, an acquisition attempt is made on the most recently acquired channel prior to an acquisition attempt on each of the remaining channels. Received signal strength estimates may also be obtained for selected channels and may be used to determine whether or not to attempt acquisition on these channels.
Abstract:
Systems and techniques for controlling transmission power involve receiving a first to second channel power ratio (502), receiving a first to second channel power ratio (502), adjusting the power ratio if a combined power of a plurality of channels exceeds a threshold (504), the channel as a function of the power ratio (506). It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.
Abstract:
Techniques to improve the acquisition process in a spread spectrum environment. The signals from different CDMA systems are spread with different sets of PN sequences, with the PN sequences in each set being uncorrelated to the PN sequences in the other sets. By using uncorrelated PN sequences, the likehood of detecting a pilot signal from an undesired system is reduced or minimized, and the mean time to acquisition of the pilot signal from the desired system is improved. The mobile station can attempt to acquire the pilot signal by processing the received signal with a first set of PN sequences corresponding to a first hypothesis of the particular signal being acquired. If acquisition of the pilot signal fails, a second set of PN sequences corresponding to a second hypothesis is selected and used to process the received signal. The PN sequences in the second set are uncorrelated to the PN sequences in the first set. The PN sequences for the first set can be generated based on the characteristic polynomials defined by IS-95-A, and the PN sequences for the second set can be the reverse of the PN sequences for the first set.
Abstract:
A dual-mode digital communication system for communicating an information signal during operation in frequency-modulated (FM) and multiple-access modes is disclosed herein. The digital communication system includes a dual-mode transmitter (14) for transmitting the information signal using an FM communication signal during FM mode operation, and for transmitting the information signal using a multiple-access communication signal during multiple-access mode operation. The communication system further includes a dual-mode receiver (16) for receiving the FM communication signal during FM mode operation, and for receiving the multiple-access communication signal during multiple-access mode operation. Incorporated within the dual-mode receiver (16) is a digital demodulator (96) for recovering the information signal from the received FM signal during operation in the FM mode, and for recovering the information signal from the received multiple-access signal during multiple-access mode operation. 00000
Abstract:
Un procedimiento de medición de la posición-localización en comunicaciones inalámbricas, el procedimiento que comprende: generar (510) en un punto de acceso una señal piloto (410) y una señal de referencia (460), la señal de referencia que comprende una secuencia de símbolos que no transportan datos y son conocidos por un terminal de acceso; y transmitir (520) desde el punto de acceso al terminal de acceso la señal piloto y la señal de referencia en una ranura de tiempo para ayudar al terminal de acceso en la medición de la posición-localización, en el que la señal piloto y la señal de referencia son utilizadas por el terminal de acceso para realizar la medición de la posición-localización.
Abstract:
Interference that occurs during wireless communication may be managed through the use of fractional reuse and other techniques. In some aspects fractional reuse may relate to HARQ interlaces (2202), portions of a timeslot, frequency spectrum, and spreading codes. Interference may be managed through the use of a transmit power profile and/or an attenuation profile. Interference also may be managed through the use of power management- related techniques. (Figure 12)