摘要:
Disclosed herein is a system and method for downlink beamforming that takes into account imperfect channel state information (CSI) at the transmitter when determining the steering vector used in the beamforming process. The steering vector is calculated to increase the ratio of the average power of a desired signal component to the sum of the interference power of other wireless terminals, referred to as the signal-to-leakage ratio. By accounting for imperfect CSI when calculating the steering vector, the bit-error rate for a given signal-to-noise ratio is decreased. Also disclosed is a power allocation method that improves performance of the system by increasing the signal-to-interference-plus-noise ratio for all of the wireless terminals currently communicating with the base station. The power allocation similarly decreases the bit-error rate for a given signal-to-noise ratio, especially at high signal-to-noise ratios.
摘要:
A system of physical layer packet format and signaling methods is disclosed, wherein signaling overhead is minimized in applications where multiple users share air interface resources; improving efficiency in orthogonal frequency division multiplexing (OFDM) and orthogonal frequency division multiple access (OFDMA) communication systems.
摘要:
The invention is CDMA quadrature signal technology that controls the transmit power of a CDMA signal. The CDMA quadrature signal technology receives a CDMA signal, and in response, process quadrature components of the CDMA signal to generate a power control signal. The CDMA quadrature signal technology adjusts the gain of the CDMA signal in response to the power control signal. A CDMA transmitter transmits the CDMA signal after the gain is adjusted. One example of the CDMA transmitter is a CDMA base station. Using the invention, a multi-sector CDMA base station can control power without transferring gain information to base station components for all sectors. The invention eliminates unnecessary data transfer and storage.
摘要:
A method and apparatus of signaling radio resource allocation in a wireless communication system includes transmitting at least one region boundary to a mobile station indicating a division of the time-frequency resources into at least two regions, determining a time-frequency resource assignment for the mobile station, transmitting an indication of the determined time-frequency resource to the mobile station in the same region as the determined time-frequency resource, and transmitting a packet to the mobile station using the physical time-frequency resources corresponding to the determined time-frequency resource.
摘要:
A method in a base station of transmitting control information to a mobile station includes transmitting a persistent assignment to a mobile station, wherein the persistent assignment includes a plurality of ACID indications; and transmitting a subsequent assignment to the mobile station including an ACID derived from the plurality of ACID indications. In another method, a mobile station receives control information from a base station, including receiving a persistent assignment from the base station, wherein the persistent assignment includes a plurality of ACID indications; and receiving a subsequent assignment from the base station including an ACID derived from the plurality of ACID indications.
摘要:
A method of establishing a direct mobile communications (DMC) link between a first user equipment (UE) and a second UE, where at least one of the first UE and the second UE is communicating on a first cellular link includes requesting that at least one of the first UE and the second UE participate in an evaluation procedure to determine a potential quality of a DMC link proposed between the first UE and the second UE. The method also includes receiving a report from at least one of the first UE and the second UE indicating the potential quality of the DMC link proposed between the first UE and the second UE according to the evaluation procedure. The method further includes establishing the DMC link between the first UE and the second UE if the potential quality of the DMC link exceeds a predetermined threshold.
摘要:
A transceiver and a method of transmitting data are provided. A frequency band, such as a licensed frequency band, is monitored during a sensing block. Based upon the use of the frequency band during the sensing block, a probability of non-interfering is calculated during a plurality of time periods in a subsequent inter-sensing block. The probability of non-interfering is used by the transceiver to determine a transmit power level such that the possibility of interference with licensed use on the frequency band is reduced. Embodiments of the present invention may be used to improve the transmission rate of the cognitive radio user.
摘要:
System and method for exploiting spatial spectrum holes (SSH) in the time/spectrum/location of wireless resources. A method comprises setting a directional antenna to a first transmission direction, determining a state of a spectrum band in the first transmission direction, transmitting information in the first transmission direction to the receiver in response to determining that the spectrum band state is idle and that the receiver lies within a coverage area of a transmitter, and transmitting the information in the first transmission direction to a first relay in response to determining that the spectrum band state is idle and that the receiver lies without the coverage area of the transmitter.
摘要:
System and method for scheduling spectrum sensing in cognitive radio systems. A method comprises sensing an availability of a spectrum band, computing a duration of an inter-sensing time block based on the availability of the spectrum band, and scheduling an occurrence of the spectrum sensing operation using the duration of the inter-sensing time block. Computing the duration of the inter-sensing time block based on the availability of the spectrum band allows for an optimization of communications of the cognitive radio system, thereby increasing spectral efficiency and reducing interference to licensed communications.
摘要:
A method and system is disclosed for managing resource within a predetermined soft handoff group in an OFDM based telecommunications system. Logical radio resources are separated into at least one set to support the soft handoff group and at least one set for supporting normal communication traffic. At least one physical radio resource is identified for each logical radio resource in the set for supporting the SHOG according to a predetermined mapping function so as to minimize resource collision.