113 results about "Satellite downlink" patented technology

The invention relates to video and music distribution systems and, more particularly, to a system that blanket transmits video/audio content such as movies (for example, via satellite downlink transmission) to each customer's recording, storage and playback system. Customers may preselect from a list of available movies or other content in advance using an interactive screen selector, and pay for the video/audio content that is actually viewed.

Disclosed herein is a system for rapidly resolving position with centimeter-level accuracy for a mobile or stationary receiver [4]. This is achieved by estimating a set of parameters that are related to the integer cycle ambiguities which arise in tracking the carrier phase of satellite downlinks [5,6]. In the preferred embodiment, the technique involves a navigation receiver [4] simultaneously tracking transmissions [6] from Low Earth Orbit Satellites (LEOS) [2] together with transmissions [5] from GPS navigation satellites [1]. The rapid change in the line-of-sight vectors from the receiver [4] to the LEO signal sources [2], due to the orbital motion of the LEOS, enables the resolution with integrity of the integer cycle ambiguities of the GPS signals [5] as well as parameters related to the integer cycle ambiguity on the LEOS signals [6]. These parameters, once identified, enable real-time centimeter-level positioning of the receiver [4]. In order to achieve high-precision position estimates without the use of specialized electronics such as atomic clocks, the technique accounts for instabilities in the crystal oscillators driving the satellite transmitters, as well as those in the reference [3] and user [4] receivers. In addition, the algorithm accommodates as well as to LEOS that receive signals from ground-based transmitters, then re-transmit frequency-converted signals to the ground.

A satellite or spacecraft in low Earth orbit, when in eclipse and not illuminated by sunlight, represents a low-bandwidth datastream through modulation of a source of uncollimated light, such as a set of light emitting diodes. Transmission modes include generating patterns in the color, intensity or polarization of a light source, or precise timing control of a strobe signal. A ground station tracks the satellite in a telescope, stewing the telescope to follow the satellite as it moves across the sky, recording light generated by the satellite with a light sensor such as a video camera. The datastream is regenerated through analysis of recorded video. Satellite downlink is initiated by detection of eclipse, by command via radio uplink, or in response to a periodic automatic timer. In an alternative embodiment, the satellite represents the datastream through modulation of its effective albedo or reflective flux during periods of solar illumination.

The invention relates to video distribution systems and, more particularly, to a system that blanket transmits video/audio content such as movies (for example, via satellite downlink transmission) to each customer's computer-based recording, storage and playback system. Customers preselect from a list of available movies or other content in advance using an interactive screen selector, and pay for only the video/audio content that is actually viewed.

Music is blanket transmitted (for example, via satellite downlink transmission) to each customer's user station where selected music files are recorded. Customers preselect from a list of available music in advance using an interactive screen selector, and pay only for music that they choose to playback for their enjoyment. An antipiracy WID tag” is woven into the recorded music so that any illegal copies therefrom may be traced to the purchase transaction. Music is transmitted on a fixed schedule or through an active scheduling process that monitors music requests from all or a subset of satellite receivers and adjust scheduling according to demand for various CD's. Receivers store selections that are likely to be preferred by a specific customer. In those instances where weather conditions, motion of atmospheric layers or dish obstructions result in data loss, the system downloads the next transmission of the requested CD and uses both transmissions to produce a “good copy”. In conjunction 20 with the blanket transmission of more popular music, an automated CD manufacturing facility may be provided to manufacture CD's that are not frequently requested and distribute them by ground transportation.

This specification discloses a satellite transmission system for transmission of TCP/IP compatible packets from a head end computer through a satellite uplink, an extraterrestrial satellite, a satellite downlink, and an integrated satellite receiver/router for outputting of the TCP/IP compatible packets through a port on the receiver/router onto a computer LAN or WAN. The system may include an Internet or telecommunications backchannel. The receiver becomes router enabled by means of a removable insertion Ethernet/Router insertion card inserted into a slot in the receiver, although the transmission system may be used to simultaneously transmit a variety of other services through the receiver by use of other service slots in the receiver. The Ethernet/Receiver supports the IGMPv2 Multicasting (querier and non querier modes), standard TCP/IP (including UDP and Telnet), and SNMP protocols.

The invention relates to integrated high-speed remote sensing data receiving and processing equipment. When the equipment is used to receive data, satellite downlink serial data are converted into parallel data through serial-parallel conversion and are sent into a frame synchronous processing module for frame synchronous treatment, frame synchronization characters are searched, fault-tolerant parameters are calculated, frame synchronization signals are generated according to the frame length and the frame synchronization characters, and the frame synchronization signals and data frame are sent to a combined decode module. The combined decode module performs descramble, RS decoding and CRC check processing on the data frame according to the frame synchronization signals, and sends the data to a cache. The data in the cache are subjected to data synthesis and wave filtering processing to be sent into a data distribution module. The data distribution module sends the transmitted data into a load imaging and processing module for format analysis processing, performs classified processing on the data according to load category, and displays the data in real time. When the data are sent, uplink data are sent into the cache through a data distribution module, a combined coding module reads the data from the cache, performs scrambling, RS coding and CRC check processing on the data, sends the data into a parallel-serial conversion module, converts the data into the serial data and transmits the data to a satellite.

The invention relates to video distribution systems and, more particularly, to a system that blanket transmits video/audio content such as movies (for example, via satellite downlink transmission) to each customer's computer-based recording, storage and playback system. Customers preselect from a list of available movies or other content in advance using an interactive screen selector, and pay for only the video/audio content that is actually viewed.

A power gated variable hop cycle beam laydown (700) manifests itself as first cells (C, D) supported by a first hop cycle, second cells (G, H) supported by a second hop cycle, and transition cells (E, F) supported by a transition hop cycle. The transition hop cycle uses power gating to transition the laydown (700) from cells (C, D) operating at the first hop cycle to cells (G, H) operating at the second hop cycle. To this end, the transition hop cycle power gates its downlink beam for a portion of time needed to reduce interference between nearby (e.g., adjacent) cells.

The invention discloses a dual-mode positioning time-service type receiver for a compass satellite and a global positioning system (GPS) satellite. The receiver comprises an antenna module, a radio frequency channel module, a compass processing module, a GPS processing module and an expansion board module, wherein the antenna module comprises a compass receiving antenna, a compass transmitting antenna and a GPS receiving antenna; the compass receiving antenna is used for receiving a compass satellite downlink signal; a compass downlink radio frequency navigation signal is acquired by filtration of a filter and amplification of a compass low-noise amplifier; the compass transmitting antenna receives the signal which is transmitted by a compass power amplifier and transmits a signal to the compass satellite in the sky; and the GPS receiving antenna is used for receiving a GPS satellite downlink signal. The invention provides the receiver which receives the signals of the compass satellite and the GPS satellite simultaneously, so that functions of compass time service, compass positioning, GPS time service and GPS positioning can be realized, the receiver is independent of the GPS, and the safety and stability of civil basic industries of our country are improved.

The invention relates to video distribution systems and, more particularly, to a system that blanket transmits video/audio content such as digital data (for example, via satellite downlink transmission) to each customer's computer-based recording, storage and playback system. Customers preselect from a list of available digital data or other content in advance using an interactive screen selector, and pay for only the video/audio content that is actually viewed.

The invention discloses a navigation signal integrity assessment method. According to the invention, navigation satellite downlink navigation signal monitoring data are used to carry out integrity risk assessment, and an operable and easy effective method is provided for spatial signal integrity indicator assessment. According to the invention, a downlink navigation signal is used to acquire a spatial signal health word sequence and a spatial signal real-time user ranging error. According to the spatial signal real-time user ranging error, a spatial signal integrity monitoring state sequence is acquired. When an available signal health word becomes unavailable, a signal alarm event is defined. When an available signal integrity monitoring state sequence becomes unavailable, an abnormal monitoring event is defined. Finally, the signal alarm event and the abnormal monitoring event are combined to compare the consistency of the spatial signal health word sequence and the spatial signal integrity monitoring state sequence to assess the navigation signal integrity.

The invention discloses a modulation performance test method for a navigational satellite binary offset carrier signal. The modulation performance test method comprises the following steps of: firstly, carrying out direct A/D sampling on a BOC (binary offset carrier) modulation navigation signal of a navigational satellite downlink transmission microwave frequency band; then, carrying out variable-frequency filtering and hilbert transform on the signal in a numeric field; carrying out quadrature demodulation, channel gain compensation and phase compensation processing in digital communication, and filtering by a measurement filter to obtain measured data; carrying out symbol detection, reference signal generation processing and reference filtering on the measured data to obtain reference data; and calculating the reference data and the measured data to obtain a parameter and a signal graph which reflects the base band modulation performance. The BOC carrier modulation signal is processed in the numeric field by the modulation performance test method. Because a BOC single sideband frequency spectrum is extracted in the numeric field, the problem that the BOC signal can not be subjected to the modulation characteristic test through a vector signal analysis method because of subcarrier can be solved.

The invention provides a method for combining a tri-band code wave pseudorange with a carrier phase in satellite navigation and positioning, relating to the technology of the satellite navigation and positioning. The method comprises the following steps of: using terminal equipment to receive the satellite downlink three code wave pseudoranges and the carrier phase; obtaining a code wave combined pseudorange and a carrier combined phase according to an integral coefficient combination, selecting a positive combination coefficient or a negative combination coefficient according to the principle that the time which is influenced by an ionosphere for closing to and solving ambiguity is short, and fast solving the ambiguity by the positive combination or the negative combination; and according to the principle that an ionosphere influence in a satellite-ground distance can be fast removed, selecting the combination coefficient to set up a double positive combination carrier wave which is used for removing the ionosphere influence in the satellite-ground distance, and using more than four (including four) pseudorange observation equations to solve the real position of the receiving terminal. The invention can set up a new system which not only can realize the high dynamic state of the code wave but also has the high precision of the carrier wave.

A multiplexer and a method for chip-synchronous code-division multiple access (CDMA) signals produces a constant envelope signal. The output signal of the multiplexer permits use of a saturating (Class C) high power amplifier (HPA) resulting in a net increase in effective transmitter power usage. This multiplexer applies to a variety of CDMA spread spectrum modulation formats and has many applications, such as the IS-95 forward link interface, and CDMA and CDMA/FDMA (frequency-division multiple access) applications, including general cellular base station forward traffic channels, cellular subscriber station multiple-channel reverse traffic channels (e.g. IS-95 subscriber Internet access) and satellite downlinks.

A method in which a satellite or a terrestrial earth station that is included in a satellite communication system that shares a frequency resource with a terrestrial communication system allocates a frequency resource is provided. The satellite divides an area of a first satellite beam into at least one sector. The satellite determines a first sector in which a satellite terminal is located among the at least one sector. The satellite determines a second sector corresponding to the first sector among at least one sector that is included in a first terrestrial cell. The satellite allocates at least one of first frequency resources for the second sector to the satellite terminal. The first terrestrial cell is located within an area of a second satellite beam adjacent to the first satellite beam.

The invention provides a satellite telemetry parameter allocation and scheduling method, including: step 1, the upper computer collects the whole satellite telemetry parameters from the lower computer, and the collection period is equal to the operation cycle of the upper computer; step 2, designs the telemetry frame format, and divides into fixed telemetry areas In the subcontracting telemetry area, the upper computer performs grouping according to the format of the telemetry frame; step 3, design a large table of telemetry data frames, and the upper computer performs grouping and downloading of telemetry data according to the large table of telemetry data frames. The present invention realizes the dynamic scheduling capability of satellite downlink telemetry data through the method of centralized allocation of telemetry parameters of the satellite upper computer, and can conveniently increase the downlink rate of the telemetry parameters of the tested system through the way of uplink injection during the satellite test process, It can more effectively judge the state of the test system, and can focus on downloading different telemetry parameters according to the different stages of the satellite in orbit, and realize the ability to download key telemetry parameters in different working modes.

The invention discloses a rapid satellite locking method of a portable satellite receiver. Coarse tuning contains the following steps: position of the receiver is determined; a satellite which is expected to be locked is selected; pitch angle, azimuth angle and polarization angle of the satellite relative to the receiver are calculated; and angle of the receiver is adjusted manually. Fine tuning contains the following steps: a downlink beacon signal of the satellite is received and satellite signal power within adjustable bandwidth is calculated; signal maximum power point is obtained; pitch angle and azimuth angle of the receiver are finely-tuned so as to be directed at the maximum power point; and polarization angle is finely-tuned and the maximum power point is observed, and the polarization angle which maximizes power is selected. An interface of a visualized terminal displays signal intensity within bandwidth during the fine-tuning process at real time and visually shows whether the result of the fine-tuning operation is accurate. The fine-tuning operation is convenient and fast. The downlink beacon signal of the satellite is received so as to realize measurement of the signal intensity. It is not necessary to transmit signals by antennas. The influence of adjacent satellite interference can be avoided effectively. Accuracy of satellite signal intensity measurement is higher.

The invention discloses communication satellite frequency spectrum monitoring equipment and a frequency spectrum acquisition and feature identification method thereof, and belongs to the technical field of satellite communication and frequency spectrum monitoring. The equipment realizes long-term monitoring of GEO communication satellite signals, acquires and automatically stores each satellite signal spectrogram in real time, completes statistical analysis of resource utilization and carrier distribution related to each satellite signal, and provides a basis for resource scheduling and network optimization of a satellite communication system; effective identification of satellite carrier signal parameters is realized, legality inspection of carrier signals is completed, an alarm is givenin time when abnormity is found, and support is provided for autonomous operation and troubleshooting of the system; and interference monitoring of satellite signals is realized, accurate identification and automatic alarm of interference parameters are completed, and a reference is provided for anti-interference decision making of the system. Two paths of satellite downlink signals within the frequency range of 70-6000MHz can be received at the same time, and the functions of frequency spectrum generation, parameter identification, interference monitoring and the like are completed on the received signals.