摘要:
A signal structure for use in D2D communications is described. In one embodiment, a preamble for automatic gain control at the receiver end is included in the transmitted signal. Techniques for scheduling of D2D transmissions using carrier sensing multiple access (CSMA) and a power control schemes for interference management are also described.
摘要:
An ultrasound and radio frequency technology is used to implement presence sensor capability for wireless devices such as, a laptap device. For example, the laptap device connects to a station device through a WiFi signal. In this example, the WiFi signal may include a data packet that synchronizes internal clocks of the laptap device with the station device. Further, the data packet may include transmitting time information for an ultrasound audio signal generated by the station device. The ultrasound audio signal is received by the laptap device that calculates time of flight (TOF) of the ultrasound audio signal. The TOF may be used to determine actual distance of the wireless device (e.g., laptap device) to the station device.
摘要:
Embodiments of an OFDM transmitter and method of reducing the effects of interference on subcarriers in an OFDM system by symbol loading are disclosed herein. A linear transformation is performed on a group of two or more input data symbols to generate a corresponding two or more output data symbols. Each of the output data symbols has an increased number of constellation points and are configured for transmission within one of the different signal dimensions using two or more antennas. Each of the two or more output data symbols carry the information of each of the input data symbols of the group. This coding together of input data symbols that are mapped to different signal dimensions may provide improved reliability against fading and severe interference. The different signal dimensions may comprise a frequency, a time and/or a space dimension.
摘要:
Embodiments of the present invention may help facilitate improved performance for high throughput, mobile wireless networks, e.g., IEEE 802.16m, mobile implementations for 3GPP Long Term Evolution (LTE) including LTE advanced mobile phone networks, and other types of high bandwidth networks. In some embodiments, provided are orthogonal sequences with desirable correlation properties for, e.g., 4-6 bits of information, among other things, typically achieving improved performance at varied vehicle speeds. In some embodiments, correlation distances for 6 bits may be less than 3.86, for 5 bits may be less than 3.12, and for 4 bits may be less than 1.95. Additionally, in some embodiments, dedicated coding for PFBCH information may be provided to achieve improved performance for most (if not all) information bits at a relatively wide range of vehicle speeds. Different code sequences for different tiles in one PFBCH channel may be applied for same messages to overcome error floors in high speed scenarios.
摘要:
A multi-resolution codebook is used to provide quantization for channel related information in a wireless network that supports both single-user MIMO and multi-user MIMO. The multi-resolution codebook may include a higher resolution “fine” codebook for use with MU-MIMO subscriber stations and a lower resolution “coarse” codebook for use with SU-MIMO subscriber stations. A tracking codebook may also be used to provide quantization for updates to channel related information. In at least one embodiment, the tracking codebook includes a number of unit vectors (or orthogonal matrices) disposed upon a sphere cap.
摘要:
A method and a system that multiplies a beamforming matrix by a unitary matrix that does not change the subspace of the beamforming matrix for form a converted matrix having a lower left triangle of zeros. A first column vector having a fewest number of elements of the converted matrix is quantized using a codebook and represented by a first codebook index. A Householder matrix is determined from the quantized first column vector and the converted matrix is multiplied by the Householder matrix. Quantizing, determining a Householder matrix from further column vectors of the converted matrix using a codebook and representing each respective column vector by further corresponding codebook index, and multiplying the converted matrix on the left by the determined Householder matrix for each respective column vector are recursively repeated. The first codebook index and further codebook indices are transmitted to a remote station for use in beamforming.
摘要:
Embodiments of an apparatus and system are described for a coaxial antenna. An apparatus may comprise, for example, an integrated circuit and a coaxial cable coupled to the integrated circuit and arranged to operate as an antenna, the coaxial cable comprising an inner conductor layer and at least one insulator layer, wherein one or more portions of the inner conductor layer are exposed to allow the exposed inner conductor layer to operate as a radiating element for the antenna. Other embodiments are described and claimed.
摘要:
Embodiments herein may provide an apparatus, comprising an antenna, the antenna including a same radiating element fed by more than one in-line-filter cables with complimentary pass and rejection bands, wherein the more than one in-line-filter cables have periodically inserted discontinuities in coaxial cables to create band rejection filter functionalities.