Abstract:
PROBLEM TO BE SOLVED: To make it possible to reconstruct at low cost and lightweight antenna coverage in a specific area on ground by connecting a receiving switch matrix to a beam former connected to a receiving element array and selecting a beam port by a switch controller connected to the switch matrix. SOLUTION: A communication payload 22 in a static satellite system 20 receives an active beam signal to be sent to a transmitting switch matrix 24 and selects a beam command to be outputted to a switch controller 23. The controller 23 receives the beam command and selects plural beam ports for orthogonal beam formers 26, 27. The matrix 24 receives active beam signals from the former 26 and a transmitting phase adjusting array 28 for transmitting a radio frequency(RF) signal. A receiving matrix 25 receives a signal from the former 27 and transmits plural active beam signals to the payload 22.
Abstract:
PROBLEM TO BE SOLVED: To realize the efficient satellite communication system for hybrid satellite group at a low cost where defects of each satellite are overcome and features of each satellite are best utilized. SOLUTION: Satellites 110, 120 adopting two or more different forms are connected to a system control center 140 through control links 105, 135. The satellites 110, 120 of the different forms are connected also to subscriber equipments 150 via subscriber links 155, 145. The satellites 110 of a 1st form are interconnected by using an upper inter-satellite link 115. The satellites 120 of a 2nd form are interconnected by using a lower inter-satellite link 125. The control service and other services that are not sensitive to a time delay are served by using a communication channel set up by using the satellites 110 of the 1st form. The services that are sensitive to a time delay are served by using a communication channel set up by using the satellites 120 of the 2nd form. No inter-satellite link is installed between the two different satellite groups.
Abstract:
PROBLEM TO BE SOLVED: To attain the increase of user capacitance by increasing the number of usable channels inside respective cells by allocating communication channels between adjacent cells having overlap areas to be mutually interferred in a cellular communication system. SOLUTION: A plurality of communication channels are divided into a non- overlapped set and an overlapped set, and the communication channels inside the interference set are allocated to non-overlapped areas 111, 121 and 131. The overlapped area of cells 110 and 120 is divided into 112 and 122, the non- interference communication channel is divided into 1st and 2nd overlapped sets, and the 1st and 2nd overlapped sets are turned into non-interferred or orthogonal state. The 1st overlapped set is allocated to the cell 110 and used inside the overlapped area 112, the 2nd overlapped set is allocated to the cell 120 and used inside the overlapped area 122, and the service of the areas 112 and 122 is provided through the same base station of a transceiver for providing communication to the areas 111 and 121. Thus, since the usable channels are divided and allocated between the non-overlapped set and overlapped set of communication channels, the number of usable channels can be increased.
Abstract:
The present invention provides a basic platform/architecture for customer premises equipment (CPE) for use in communications systems such as satellite communications systems. The present invention provides a CPE (400) which is capable of transferring data to and from a plurality of different systems having different infrastructures associated therewith. This data is processed to a data form that is supplied to a multimedia services core processor (404) which is responsible for data, service and network management functions and for providing a plurality of features such as security and accounting - to name a few. The output of the core processor is supplied, via an open interface architecture, to one or more of application specific variants (406) for coupling to one or more corresponding user equipment. Such application specific variants may provide appropriate interface to user equipment such as televisions, personal computers and video conferencing units.
Abstract:
A satellite-based, world-wide cellular messaging system (5) transmits paging messages to pagers via multiple beams (30). A message unit (2) monitors a multi-frequency, TDMA paging transmission and, in response to the number of transmission frequencies in use during a given time, switches to a predetermined one of the frequencies, dependent upon the contents of a reprogrammable table stored in the message unit. Information within the paging transmission specifies what frequencies will be used and when a paging transmission will be directed at a particular pager's cell.
Abstract:
A satellite-based, world-wide cellular messaging system transmits paging messages to pagers via multiple beams. A message unit monitors multiple beams, recording the visit information for each beam, and ultimately determines the optimum beam to monitor for messages. The message unit, which conserves battery resources by entering into a sleep mode, synchronizes quickly to its message block when it awakes.
Abstract:
Methods (70, 100, 150) efficiently assign user channels in a LEO (low-earth orbit) telecommunication system (10). These methods (70, 100, 150) adapt the channel reuses based on system load or demand. These methods (70, 100, 150) achieve high capacity and minimize interference for the particular situation. Since these methods (70, 100, 150) are adaptive, they adjust to maintain efficient operation as the load conditions change.
Abstract:
A packet data communication system (10) where multiple users (87) can access the same channel (22) to maximize an efficiency of the communication system (10). Each channel (22) is divided into time slots. Each time slot is allocated to a user based on the user's request (303) for time slots and the availability of time slots. If time slots are available, then the system (10) will inform the user (87) and allocate the time slot to the user (87, 305). If there are no available time slots, then the system (10) will inform the user (87) that no time slots are available and access to the system's channel is denied. The user (87) will continue to request access (303) to the system (10) as long as the user has data packets to send.
Abstract:
A communication system (10), having dynamic nodes such as satellites (12), require narrow-tolerance communication parameters such as timing and frequency. A voice subscriber unit (26) establishes a traffic channel (17) by negotiating communication parameters. A user of voice subscriber unit (26) generates inherent voice pauses in communications. A data subscriber unit (31) possess a datagram for delivery through communication system (10). Instead of negotiating a dedicated traffic channel for delivery of the datagram, data subscriber unit (31) monitors an active voice subscriber unit (26) and determines if the communication parameters used by voice subscriber unit (26) are compatible for data subscriber unit (31). Data subscriber unit (31), upon detecting a voice pause by voice subscriber unit (26), transmits the datagram to satellite (12) using the negotiated communication parameters of voice subscriber unit (26).
Abstract:
Information packets are error encoded for transmission through a communication channel (34) in a communication system (10) using a variable payload outer code and a common physical layer inner code. The variable payload outer code is selected for each packet based upon an application or service associated with the packet. Thus, less coding can be used for packets associated with error tolerant applications and more coding can be used for packets associated with error sensitive applications. A common header outer code is also used for the packets. The variable payload outer code is preferably applied at the system adaptation level within an interworking function (22, 24) in the communication system (10). The common header outer code and the common physical layer inner code are preferably applied at the data link layer.