68 results about "Link margin" patented technology

A method and system for a plurality of airplanes in flight to receive from and send to a plurality of ground stations broadcast and communication signals through a single or a plurality of geostationary satellites, wherein at least the mobile link between said airplanes and said satellite, uplink or downlink, uses the high frequency radio waves at 17 GHz or higher, such as Ka-band. The fixed link between said satellite and said ground stations may use any radio frequencies below the frequencies used to communicate between the satellite and the aircraft. The lower frequencies tend to be less susceptible to rain attenuation and hence suitable for closing the fixed broadcast and communication link. Frequencies such as C-band or Ku-band, or even Ka-band, are applied between satellite and ground such that the available link margin is sufficient to overcome rain attenuation at said ground stations. Said satellite carries a plurality of transponders that may include a plurality of frequency converters to enable the conversion between different frequencies. Said satellite generates a plurality of spot beams, shaped or unshaped, which collectively cover the flight routes of said airplanes, preferably the geodesic path between two highly populated regions.

Methods, systems, and devices are described for wireless communication at a user equipment (UE). A wireless communications system may improve UE discovery latency by dynamically selecting and switching beam forming codebooks at the millimeter wave base station and the wireless device. Selecting an optimal beam forming codebook may allow the wireless communication system to improve link margins between the base station without compromising resources. In some examples, a wireless device may determine whether the received signals from the millimeter wave base station satisfy established signal to noise (SNR) thresholds, and select an optimal beam codebook to establish communication. Additionally or alternately, the wireless device may further signal the selected beam codebook to the millimeter wave base station and direct the millimeter wave base station to adjust its codebook based on the selection.

A computer system for graphically indicating quality of Radio Frequency (RF) connection for a floor plan of a building is provided, A computer processor is configured to identify wall types and determine a wall property for a plurality of walls included in the floor plan, predict an RF signal strength from an RF transmitter positioned at a certain location on the floor plan, determine a prediction confidence level based on signal measurements, determine an RF connectivity level for respective RF receivers to be located in different areas of the floor plan based on analysis of the associated predicted RF signal strength, mounting inclination and orientation of the receiver devices, determined wall properties associated with walls located in expected paths of predicted RF signals, and an associated link margin, and provide a GUI on a computer display indicating a visualization of RF connectivity levels on areas of the floor plan.

Disclosed herein are techniques for power management in wireless networks. Based upon receipt of an indication of the link margin of a receiving wireless device, a transmitting wireless device may adjust its transmit power commensurate with the link margin. The indication of the link margin may be transmitted from the receiving wireless device to the transmitting wireless device periodically. Alternatively, the receiving wireless station may provide the indication of the link margin in response to information received from the transmitting wireless device. In this instance, the indication of the link margin may be included in a piggyback acknowledgement (ACK) frame conventionally used to acknowledge receipt of the information transmitted by the transmitting wireless station.

A random access method in a mobile communication system, the random access method for supporting random access with a cell size of about 100 kilometers (km) or more and a power limited terminal and a preamble structure thereof are provided. While a conventional long term evolution (LTE) random access preamble sequence is reused, a difference in a round-trip delay time between terminals in a large cell area may be compensated. Additionally, since higher power transmission is achieved per bandwidth, a higher link margin may be secured. Also, compatibility with resource scheduling of the conventional LTE may be maintained. Random access may be supported in a large cell, and a preamble structure of a satellite mobile communication may be implemented based on terrestrial LTE.

Satellite communication methods and systems are disclosed. Various embodiments employ dummy bursts to monitor the communication channel between a user terminal and a hub. In some embodiments, dynamic link adaptation can also be employed to optimize channel performance. In some embodiments, the link margin can be estimated based on the signal quality of a traffic or dummy burst that is received at the hub and compared with a threshold value. If the link margin is less than a first/low threshold then the hub can instruct the terminal to change any of various communication parameters according to a predetermined algorithm to mitigate channel fading. If the link margin is greater than a second/high threshold then the hub can instruct the terminal to change any of various communication parameters according to a predetermined algorithm to reduce overcompensation for channel fading.

Disclosed is a link margin adaptation method using feedback information of a wireless communication system. For transmission and reception of data between two nodes of the wireless communication system, a transmission node requests a receiving node to transmit a link margin. The transmission node receives the link margin, and selects one of a white noise table or a delay spread table according to a delay spread value between the two nodes. Then, the transmission node adapts a link between the two nodes to a transmission mode and decides a transmission rate to transmit data at the decided transmission rate, thereby improving transmission capacity of the wireless communication system, obtaining the optimum link state, extending power utilization time of stations, and reducing interference between stations.

A communication system for mobile platforms includes mobile platforms with transceivers identified by Internet Protocol (IP) addresses. A satellite relays a forward link from a ground station to the mobile platforms. The forward link contains IP packet data that is modulated by variable length orthogonal (VLO) spreading codes and that has different information data rates. The VLO spreading code for each IP packet is selected to optimize a desired link margin of the IP packet that is received by the addressed transceiver. The IP packets can also be modulated using a pseudonoise (PN) spreading code. Forward error correction (FEC) may also be applied. The transceivers include a feedback circuit that generates an E_b/N_o estimate.

The invention discloses a near-earth remote sensing satellite self-adaptive variable code modulation data transmission system and method, belonging to the field of satellite overall design. The invention provides a variable code modulation data transmission system and method based on a DVB-S2 protocol, which fully utilizes link resources for the near-earth remote sensing satellite data transmission, adopts a variable code modulation (VCM) system, fully utilizes the system link margin, and improves the satellite star-ground data transmission efficiency; and the optimal code modulation mode is selected by means of the DVB-S2 protocol under the condition of satisfying a bit error rate and the link margin, so that the amount of effective information transmitted per unit time is the largest. The near-earth remote sensing satellite self-adaptive variable code modulation data transmission method provided by the invention can maximize the adaptation to changing channel conditions and channel capacity due to orbital changes of the near-earth remote sensing satellite, and transmit more data information on a limited spectrum resource, which is very suitable for the data transmission of the near-earth remote sensing satellite to the ground.

Low-latency satellite Internet service from a commercial off-the-shelf two-way satellite Internet system for aircraft under marginal communications link conditions is provided. One or more identical Internet requests each having a unique ID are sent in rapid succession from the aircraft. The one or more identical Internet requests are received at a satellite and sent to a network operations center (NOC) where they are forwarded over the Internet to an appropriate Web site. Identical Web pages are retrieved for the identical Internet requests by the NOC and transmitted to the satellite and then relayed to the aircraft. The requested Web page data is fused for the requested Web pages into a single Web page response in accordance with the unique IDs in the server for viewing by a client PC with low-latency when a failure in transmitting and receiving identical Internet requests and requested Web pages occurs.

A wireless communication system that provides energy efficient, high bandwidth and low cost wireless communication. In one embodiment, the communication system utilizes a fan out, pencil beam arrangement in which electro-magnetic energy is transmitted from a hub to customer premises equipment (CPE) with a fan or similar antenna and from the CPEs to the hub via pencil beam antennas. The pencil beam antennas provided higher link margin. The hub may include a shared aperture antenna device for receiving pencil beam transmissions from the CPEs. A shared aperture antenna device may also be used for transmission from the hub to the CPEs.

The invention provides a self-adaptive distance data transmission method for an aircraft-mounted terminal and aims to provide a data transmission method capable of improving transmission link utilization rate and data transmission efficiency and also provides a self-adaptive implementation method for the data transmission between the aircraft-mounted terminal and a data transmission receiver. The self-adaptive distance data transmission method is realized through the following technical scheme: an aircraft inertial navigation system provides inertial navigation data for the aircraft-mounted terminal in real time through a serial port, a link margin estimator of the aircraft-mounted terminal calculates the distance between an aircraft and the data transmission receiver in real time according to the inertial navigation data and works out the system margin of the data transmission link according to the stored data transmission receiver relevant parameters, the data transmission link parameters and the parameters such as the EIRP (effective isotropic radiated power) value of the antenna of the aircraft-mounted terminal, the aircraft-mounted terminal automatically selects data transmission speed, carries out coded modulation on data in different data transmission speeds through an encoder and a modulator, and transmits the data to the data transmission receiver after up-conversion and amplification processing.

A method for analyzing the working performance of a damaged satellite-earth data transmission antenna comprises the steps of (1) calculating the equivalent isotropic radiated power (EIRP) of a satellite according to the output power of a satellite transmitter, satellite antenna gain and the transmission channel loss value; (2) calculating the maximum slant range R of signal transmission according to the mean terrain level of a satellite and the minimum elevation of a ground receiving antenna; (3) calculating the free space loss Lf of a signal according to the downlink carrier frequency of the satellite data transmission signal and R; (4) calculating all transmission losses L of the data transmission signal according to the atmosphere loss, the directivity loss of the receiving antenna, the polarization loss and atmosphere value of the receiving antenna and Lf; (5) calculating the bit signal to noise ratio of a received signal by means of the coding gain, the transmission code rate, the coding rate and the link margin; (6) calculating the bit signal to noise ratio actually needed by the received signal according to bit error rate requirements so as to obtain the channel margin, wherein if the margin is positive, the overall performance of the damaged data transmission antenna can still meet the requirements of a system, and the working performance of the data transmission antenna is affected otherwise.

Disclosed is a low-rate data transmission method in an LTE based satellite radio interface, which can secure a large number of low-rate data channels which can simultaneously access and increase frequency efficiency while providing compatibility with the existing LTE radio interface through a transmission technique which can secure more link margins in communication between portable terminals (handheld type terminals) without changing a basic LTE transmission frame structure in a satellite system requiring high transmission power.

The present invention utilizes a dual polarization reception system (200) that utilizes the energy available in orthogonal polarizations to effectively increase link margin, thereby allowing for adequate signal quality reception in difficult environments. A co-polarized and a cross-polarized signal are separately downconverted and demultiplexed. The signals from each demultiplexed output are then sampled and weighted. The weighted samples for each polarity are combined in soft decision combining/decoding circuitry (255, 360), and this circuitry determines the most likely state of a received symbol's transmitted value.

A method for determining receiver coupling efficiency includes varying optical power inputted into a half active optical cable to determine a maximum optical power at which the TIA squelches and determining a receiver coupling efficiency by calculating a ratio of a threshold optical power to the maximum optical power at which the TIA squelches. A method of determining link loss in a channel includes varying optical power of a light source to determine the maximum optical power at which the TIA squelches and determining the link loss in the channel by subtracting the maximum optical power from the threshold optical power. A method of determining link topology includes selecting a pattern of optical powers and matching a pattern of squelched and non-squelched outputs with the pattern of optical power. An active optical cable includes memory storing a value related to an initial link loss of the active optical cable.

A system and method for conducting dynamic RF-link margin tests in an electronic toll collection for non-stationary vehicles travelling up to highway speed. The system maintains a list of candidate transponders and, during the course of a normal toll collection, if a transponder is on the list then the system schedules a margin test for a later handshake in the capture zone. At a location at or near the peak margin test the system conducts a margin test during one or more of the reader-transponder handshakes. The attenuation may be dynamically controlled by the system using a variable attenuator in the RF path from the reader RF module to the antenna. Distributing the margin measurement over multiple passes of a vehicle through the capture zone provides for a highway speed method of measuring link margin.

The invention discloses a data center network energy consumption and service quality optimization method based on reinforcement learning. The method comprises the steps of constructing data center network energy consumption and service quality optimization model based on a deep reinforcement learning framework; respectively taking the link utilization rate, the completion time related performancecalculated by the network performance and the link margin ratio as the state, reward and action of the optimization model; and then adjusting the flow of the data center network according to the linkmargin ratio output by the optimization model, so that the time volatility of the data flow and the spatial distribution characteristic of the data flow are both considered in the adjustment process,and the energy efficiency of the data center network is improved while the FCT is ensured.

Certain aspects of the present disclosure generally relate to wireless communications and, more particularly, systems and methods for a link margin procedure that accommodates reporting link parameters, such as link margin, for multiple streams.