Abstract: The invention relates to piggyback secondary payloads, a device for and a method of attaching piggyback secondary payloads, including a primary satellite and at least one secondary payload, such as a deployable microsatellite, affixed instrument package or the like, wherein the secondary payload is mounted on the nadir end of the primary satellite, preferably employing a universal adapter between the primary satellite and the at least one secondary payload.

Abstract: The invention relates to a piggyback satellite, a device for and a method of attaching piggyback satellites with multiple payloads, including a primary satellite and at least one secondary payload, such as a deployable micro satellite, affixed instrument package or the like, wherein the secondary payload is mounted on the nadir end of the primary satellite, preferably employing a universal adapter between the primary satellite and the at least one secondary payload that releases at least one secondary payload or the like in a certain orbit in space for allowing the secondary payload to continue its journey independently in space for transmitting and receiving data.

Abstract: The invention relates to a piggyback satellite, a device for and a method of attaching piggyback satellites with multiple payloads, including a primary satellite and at least one secondary payload, such as a deployable micro satellite, affixed instrument package or the like, wherein the secondary payload is mounted on the nadir end of the primary satellite, preferably employing a universal adapter between the primary satellite and the at least one secondary payload that releases at least one secondary payload or the like in a certain orbit in space for allowing the secondary payload to continue its journey independently in space for transmitting and receiving data.

Abstract: The invention relates to piggyback secondary payloads, a device for and a method of attaching piggyback secondary payloads, including a primary satellite and at least one secondary payload, such as a deployable microsatellite, affixed instrument package or the like, wherein the secondary payload is mounted on the nadir end of the primary satellite, preferably employing a universal adapter between the primary satellite and the at least one secondary payload.

Abstract: A method and system of performing IP multicast includes a client at one of many downstream networks that sends a request signal to an upstream network via a return channel (e.g., the Internet), and the upstream network sends the request to a media server. The media server, and for live data, a media encoder, processes a media stream to generate a real-time IP multicast communication that is output to a unidirectional satellite that transmits the IP multicast communication to the client without delay via the downstream network, and can convert the IP multicast to unicast. The bidirectional return channel allows the source to calculate billing information based on client usage statistics, and transmits confirmation acknowledgement based on a confirmation request from the upstream network. Because the routing configuration is transparent to the rest of the network, the invention applies to multi-hop networks on both sides of the satellite link.

Abstract: A method and system of communication between an IP backbone Internet Service Provider (ISP) and remote Internet service providers via a shared channel on a satellite is provided. At a first router coupled to the IP backbone ISP, a static route for an IP packet of the IP backbone ISP is determined based on a media access control (MAC) address of a destination router of the IP packet. The IP packet is encapsulated and transported in a frame having the MAC address of the destination router based on the static route. Next, the frame/IP packet is received in a second router coupled to the remote ISP, which either drops the IP packet prior to reaching the remote ISP, or transports the IP packet to a final destination in the remote ISP, based on the MAC address of the IP packet destination and a MAC address of the second router.

Abstract: A burst tone range processing system for determining the distance between a ranging station and a signal re-transmitting target device, generates a burst tone signal of finite duration and transmits the signal along a delay transmission path from the ranging station to the target and along a reference transmission path within the ranging station. The transmitted signals are received from the reference and delay paths and assigned time tags. The signals are then correlated and the time tags assigned to correlated signals are compared.

Abstract: The steady state condition of a subject product is projected using transient data developed through actual or simulated tests or operations. The transient data represent the monotonic or cyclic property states of the product while subjected to environmental or operational conditions. A first and second property state value corresponding to the transient data for selected times within the test period are identified. A first and second rate-of-change value corresponding to the change in the property states at the selected times are then computed. A time constant value is next computed by applying the time interval and the first and the second rate-of-change values to a time constant function. A projected steady state condition value is next computed by applying the second rate-of-change value, the second state value and the time constant value to a projected steady state conditions function. The projected steady state condition value is compared with a previously computed projected steady state condition value.

Abstract: A liquid detector for thin-walled tanks Operating in a zero gravity environment (e.g., outer space). The liquid detector includes a small heater, such as a 1-watt patch heater, and two thermistors positioned on either side of the heater and diametrically opposed to each other. The heater and two thermistors are located on the outside of a propellant tank of, for example, a satellite. One of the thermistors is positioned directly over a region where a propellant management device retains liquid. The other thermistor is spaced apart from the region, while the heater is proximate to the region. In operation, the heater is activated for a short period of time and the change in temperature at each of the two thermistors is observed. The temperature of a thermistor located over a spot having liquid propellant in contact with the tank wall will increase less than the temperature of the thermistor located at a spot where no liquid propellant is present.

Abstract: A single- or dual-circularly polarized earth station antenna is converted into a single- or dual-linearly polarized earth station antenna for accessing linearly polarized satellites. In a first embodiment, a free-space meander line polarizer providing a 90.degree. differential phase shift between two orthogonal polarizations is disposed in front of the earth station antenna feed system. In a second embodiment, a power dividing (transmit) or power combining (receive) network operates in conjunction with differential phase shift circuits to achieve the polarization conversion.

Abstract: A thermionic energy conversion method and apparatus is disclosed that eliminates or substantially reduces deficiencies caused by space charge or thermal radiation losses from the emitter to the collector. The method and apparatus uses an acceleration electrode having an aperture and disposed in the space between the emitter and collector. A high positive voltage is applied to the acceleration electrode to generate a positive electrostatic field. The shape of the facing surfaces of the emitter and collector and the shape of the acceleration electrode shape the electrostatic field to cause boiled-off electrons from the emitter to be accelerated and converged so that they all pass through the aperture without impinging on the acceleration electrode.

Abstract: A nearly instantaneous companding processor uses variable precision block quantization for reducing the digital transmission rate of speech signals while at the same time maintaining a high quality signal in a digital communication system. The variable number of bits which are used to encode each sample is controlled as a function of the maximum sample magnitude in a block of N samples. This technique takes advantage of the amplitude probability density function of a speech signal to thereby reduce the quantizing noise without increasing the transmission rate.