Patents Assigned to Comsat
  • Publication number: 20210306068
    Abstract: A network management systems (NMS) and methods for automating aircraft wideband streaming L band providing dedicated high data rate communication links from an aircraft fitted with an approved L-band terminal and antenna over a satellite communication network, such as the Inmarsat Swift Broadband network. The systems and methods allow for modifying the L-band terminal wiring to inject a dedicated single channel per carrier (SCPC) signal from an external modem to achieve return data rates in the range of several Mbps over a dedicated leased satellite bandwidth.
    Type: Application
    Filed: June 14, 2021
    Publication date: September 30, 2021
    Applicant: COMSAT, INC.
    Inventors: RODRIGO GOMEZ, TIMOTHY W. KNOWLES, BEN T. VUONG, LASSE THORBRO-STEENBERG
  • Patent number: 11038584
    Abstract: A network management systems (NMS) and methods for automating aircraft wideband streaming L band providing dedicated high data rate communication links from an aircraft fitted with an approved L-band terminal and antenna over a satellite communication network, such as the Inmarsat Swift Broadband network. The systems and methods allow for modifying the L-band terminal wiring to inject a dedicated single channel per carrier (SCPC) signal from an external modem to achieve return data rates in the range of several Mbps over a dedicated leased satellite bandwidth.
    Type: Grant
    Filed: October 8, 2019
    Date of Patent: June 15, 2021
    Assignee: Comsat, Inc.
    Inventors: Rodrigo Gomez, Timothy W. Knowles, Ben T. Vuong, Lasse Thorbro-Steenberg
  • Patent number: 10476582
    Abstract: A network management systems (NMS) and methods for automating aircraft wideband streaming L band providing dedicated high data rate communication links from an aircraft fitted with an approved L-band terminal and antenna over a satellite communication network, such as the Inmarsat Swift Broadband network. The systems and methods allow for modifying the L-band terminal wiring to inject a dedicated single channel per carrier (SCPC) signal from an external modem to achieve return data rates in the range of several Mbps over a dedicated leased satellite bandwidth.
    Type: Grant
    Filed: January 17, 2018
    Date of Patent: November 12, 2019
    Assignee: COMSAT, Inc.
    Inventors: Rodrigo Gomez, Timothy W. Knowles, Benjamin T. Vuong
  • Patent number: 9629055
    Abstract: A system and method for protection against loss of communication of a mobile node crossing a black spot region is disclosed. The system to prevent loss of communication with the mobile node consists of a mobile node, RF coverage map generator, black spot predictor, and a vertical handover process. The mobile node can experience uninterrupted communication across black spots. This is achieved by executing vertical handover before entering a black spot region, which is anticipated by using RF coverage maps and mobility pattern of the mobile node.
    Type: Grant
    Filed: November 9, 2014
    Date of Patent: April 18, 2017
    Assignee: Comsats Institute of Information Technology
    Inventors: Syed Mohammad Riaz Hussain, Shahzad Ali Malik, Hassan Ahmed, Shahid Ahmed Khan
  • Patent number: 7680653
    Abstract: A method and apparatus to reduce background noise in speech signals in order to improve the quality and intelligibility of processed speech. In mobile communications environment, speech signals are degraded by additive random noise. A randomness of the noise, which is often described in terms of its first and second order statistics, make it difficult to remove much of the noise without introducing background artifacts. This is particularly true for lower signal to background noise ratios. The method and apparatus provides noise reduction without any knowledge of the signal to background noise ratio.
    Type: Grant
    Filed: July 2, 2007
    Date of Patent: March 16, 2010
    Assignee: Comsat Corporation
    Inventor: Suat Yeldener
  • Patent number: 7366134
    Abstract: In a multiple-user network communication system such as a satellite-based system, or in cable or wireless systems, the system resources, such as bandwidth, code allocation, and or slot timing, are allocated to users based in part on their class of service. The allocation provides for immediate allocation of the requested resources to a user having a verified high class of service so long as the resources are abatable or can be made available by tapping a resource reserve. If only a portion of the requested resources are available, they are made available immediately. From time to time, the resources available to at least one class of service are allocated among the users of that class of service, either equally, equally up to the requested resources, equitably, or in some systematic manner.
    Type: Grant
    Filed: August 17, 2001
    Date of Patent: April 29, 2008
    Assignee: Comsat Corporation
    Inventors: Pratik Bose, Dilip S. Gokhale, Ajai Kaul, Udayan Narayan Borkar
  • Patent number: 7289063
    Abstract: The present invention uses low temperature co-fired ceramic (LTCC) technology for fabrication of micro-electro-mechnical systems (MEMS) based phase shifters. As a result, low-cost subarray modules can be constructed using LTCC, and the subarray modules (10) can be used as building blocks for large antenna arrays. In an exemplary description of the present invention, all layers of the multilayer subarray modules, including MEMS, are in LTCC. As a result, a significant cost reduction for satellite terminals using highly integrated LTCC subarray modules.
    Type: Grant
    Filed: April 12, 2002
    Date of Patent: October 30, 2007
    Assignee: Comsat Corporation
    Inventor: Amir I. Zaghloul
  • Patent number: 7262744
    Abstract: A phased array antenna (100) comprising a planar array having a plurality of modules (101,102,103). Each module comprises an integrated multilayer structure having a plurality of radiating elements (215), at least one of the layers is produced using MEMS technology. Further, each module has at least one of a plurality of phase shifters (220,221,222), a plurality of power dividers (230,231,232), a plurality of polarization circuits (and a plurality of filters (240,241,242)). The modules are coupled, both mechanically and electrically, to a distribution network (110) for distribution of DC signals and RF signals. At least one amplifier (121,122,123) is connected between the distribution network and the modules or a single amplifier is connected to the whole array.
    Type: Grant
    Filed: February 14, 2002
    Date of Patent: August 28, 2007
    Assignee: Comsat Corporation
    Inventors: Amir I. Zaghloul, Ozlem Kilic
  • Patent number: 7246143
    Abstract: A Fast Fourier Transform (FFT) arrangement for use in those situations in which not all of the outputs are desired is controlled in such a fashion that at least those multiplications (and possibly those additions) are not performed which do not contribute toward the desired outputs. The technique is usable in those situations in which the desired output signals are noncontiguous, or are in noncontiguous bins. The technique includes signal preprocessing in which the indices are adjusted so that the index for a particular stage points to those butterflies of the previous stage which contribute toward its output. The FFT is performed on the indexed data. In one embodiment, a pipelined FFT processor is controlled in a corresponding manner.
    Type: Grant
    Filed: April 9, 2001
    Date of Patent: July 17, 2007
    Assignee: Comsat Corporation
    Inventors: Zhong Hu, Prakash Chakravarthi
  • Patent number: 7213080
    Abstract: An adaptive intelligent radio module (IRM) is provided in an intelligent radio design for gateways between satellite and terrestrial networks. The intelligent radio module monitors channel signal quality at the channel units of the gateway to determine whether the quality of a channel unit is below a predetermined quality threshold. If the channel quality is greater than or equal to the predetermined quality threshold, then a standard channel unit is employed, and nominal algorithms are used to process the channel. However, if the channel quality is below the quality threshold, then a high performance channel unit is used that employs complex algorithms unique to the particular quality defect of the channel quality. Various additional functions can be performed at the receive side and the transmit side of the channel units monitored by the IRM. Further, the IRM can add or enhance existing algorithms in accordance with new technology.
    Type: Grant
    Filed: July 16, 2001
    Date of Patent: May 1, 2007
    Assignee: Comsat Corporation
    Inventors: Prakash Chakravarthi, Anupama Dharap
  • Patent number: 7154971
    Abstract: A digitally implemented demodulator (FIG. 1) produces initial detection estimates (180) and transition estimates (23) of symbols sampled in the range lying between 1 and 2 complex samples per symbols of the received carrier (14I), (14Q). In the case of detection estimate, the second-occurring of the two estimated values is selected as the correct value when there are two samples in the symbol interval. In the case the transition time estimate, the first-occurring of the two estimated values is selected as the correct timing estimate.
    Type: Grant
    Filed: February 9, 2001
    Date of Patent: December 26, 2006
    Assignee: Comsat Corporation
    Inventor: James Russell Thomas
  • Patent number: 7013137
    Abstract: This disclosure describes a method to generate large numbers of spot beams for multiple-beam satellite systems using smaller apertures. This is done by dividing the basic spot beam that has 3 to 4 dB of gain drop within the beam into a number of smaller 1-dB sub-beams. This has the effect of reducing the required peak gain for the antenna by 2–3 dB, thus reducing its size by as much as 50%. The frequency band allocated to the basic beam will be divided among the sub-beams. However, the frequency re-use among the basic beams can be maintained. Frequency allocations have to be coordinated among all beams. This concept is especially applicable to phased arrays using digital beam formers. The DBF complexity is a function of the number of array elements, and is less dependent on the number of beams. Reducing the array size, and consequently reducing the number of elements helps in reducing the complexity, power and mass of the DBF.
    Type: Grant
    Filed: July 16, 2001
    Date of Patent: March 14, 2006
    Assignee: Comsat Corporation
    Inventors: Amir I. Zaghloul, Ozlem Killic, Albert E. Williams
  • Patent number: 6963570
    Abstract: An apparatus for compressing the header of ATM cells in order to provide greater bandwidth includes means for discriminating cells/packets (1310), means for detecting header (1320), means for compressing header (1330), means for combining compressed header with payload (1350), means for discriminating compressed header cell/packet (1710), means for detecting header in compressed header and separating header from payload (1720), means for decompressing header (1730), and means for combining decompressed header with payload (1740) to form cell/packets.
    Type: Grant
    Filed: July 15, 1998
    Date of Patent: November 8, 2005
    Assignee: Comsat Corporation
    Inventor: Anil K. Agarwal
  • Patent number: 6859442
    Abstract: To efficiently transmit frame relay packets between terrestrial frame relay networks (10, 12) over a satellite/wireless network (14), the packets are processed by frame relay processors (16, 18) at both ends of the satellite/wireless network (14). Variable length frame relay packets are segmented into smaller packets called spackets. The system utilizes priority queueing and a scheduler (24) transmits the spackets over the satellite/wireless link. To enhance the quality of the satellite/wireless link, each frame contains a variable number of Reed-Solomon (RS) check bytes used for error correction. Further, several frames are interleaved before transmission over the satellite/wireless link to spread the effect of burst errors over several frames. Additionally, a header compression technique saves bandwidth by compressing a Virtual Circuit (VC) identifier of the frame relay packet into a smaller value and maps the VCs to a value as specified by the size of the compressed VC field.
    Type: Grant
    Filed: October 20, 1998
    Date of Patent: February 22, 2005
    Assignee: Comsat Corporation
    Inventors: Anil K. Agarwal, Sampath V. Kumar
  • Patent number: 6842615
    Abstract: A telecommunications network including sub-telecommunications networks for transferring information including packet data which comprises one or more mobile stations, a first sub-telecommunications network, and a second sub-telecommunications network interconnected with the first sub-telecommunications network. The network further includes a number of gateway GPRS support nodes, and one or more gateway GPRS support nodes corresponding to each of the first sub-telecommunications network and the second sub-telecommunications network. Each of the gateway GPRS support nodes is operable to provide interworking between the first and the second sub-telecommunications networks and external packet data networks. The network also includes a system controlled in accordance with a procedure for transferring packet data within a multi-country telecommunications network.
    Type: Grant
    Filed: July 16, 2001
    Date of Patent: January 11, 2005
    Assignee: Comsat Corporation
    Inventor: Oguz Angin
  • Patent number: 6839332
    Abstract: According to an exemplary embodiment an architecture for a new integrated TDMA system capable of carrying circuit data (e.g., voice, vides, ISDN), packet data (e.g., X.25, Frame Relay, Internet, LAN), and ATM cells is disclosed. The architecture may be used for satellite and wireless TDMA networks, for example. For this transmission formats for bursts (101), channels (130, 140), TDMA frames (10) are defined and an adaptation layer for the three traffic types is described. In addition, the network has to carry its own management traffic and provide timing and control information to all terminals. For this the invention defines special bursts and along with their associated properties and formats. Each burst contains a data section which is divided into a number of channels.
    Type: Grant
    Filed: October 20, 1998
    Date of Patent: January 4, 2005
    Assignee: Comsat Corporation
    Inventors: Anil K. Agarwal, Udayan N Borkar
  • Patent number: 6819658
    Abstract: A method and apparatus for providing for segmentation, reassembly and inverse multiplexing of variable sized packets and ATM cells over satellite and wireless links. Variable sized packets are divided into segments having a size equal to that of an ATM cell and are arranged in a segmentation and reassembly (SAR) frame having in its overhead an indication as to the length and unique identity of the frame, each segment also having a header that uniquely identifies the segment, the destination and the origination of the packet from which the segment originates. A terminal id is also used to identify the unit, site and control group from which the segment originates so that the information can be transmitted on the basis of available bandwidth on demand.
    Type: Grant
    Filed: March 3, 2000
    Date of Patent: November 16, 2004
    Assignee: Comsat Corporation
    Inventors: Anil K. Agarwal, Udayan N. Bokar, Moorthy N. Hariharan, Shekhar V. Patankar
  • Patent number: 6810377
    Abstract: A lost frame recovery technique for LPC-based systems employs interpolation of parameters from previous and subsequent good frames, selective attenuation of frame energy when the energy of a subframe exceeds a threshold, and energy tapering in the presence of multiple successive lost frames.
    Type: Grant
    Filed: June 19, 1998
    Date of Patent: October 26, 2004
    Assignee: Comsat Corporation
    Inventors: Grant Ian Ho, Marion Baraniecki, Suat Yeldener
  • Patent number: 6790243
    Abstract: A lithium-ion cell includes a carbonaceous anode and a lithiated metal oxide cathode, with a plastic spacer therebetween and liquid electrolyte containing lithium salts. The cell stands for a period of time aller electrolyte is added. The cell is then charged at a first current density of about ¼ mA/cm2 for at least an hour. Following the first charge, the cell stands open-circuited for at least an hour. The cell is again charged, at a current density significantly greater than the first current density, until the cell reaches a particular voltage which corresponds with the desired cell capacity, and gases are vented. After the second charge, the cell is discharged at a relatively high current density toward a particular voltage, so as to leave less active lithium ions in the anode structure. After discharge, the lithium ion cell is sealed and ready for charging by a user.
    Type: Grant
    Filed: January 7, 2002
    Date of Patent: September 14, 2004
    Assignee: Comsat Corporation
    Inventor: Hariharan Vaidyanathan
  • Patent number: 6744836
    Abstract: The present invention relates to burst mode digital communication systems where data transmission is preceded by a preamble for acquisition of carrier and clock synchronization using maximum likelihood (ML) principle. The preamble is sampled and the set of samples obtained is processed using the optimization algorithms of the present invention to provide the ML timing estimate. The optimization algorithms in the present invention consist of three parts. The first part deals with isolating the desired optimal estimate from non-optimal extremes satisfying the same necessary condition, and provides the initial conditions for activating the binary search schemes. The second part performs the binary search for the optimal timing estimate that guarantees the convergence. On the basis of the obtained iterative sequence, the last part constructs a more rapidly convergent sequence to obtain the ML symbol timing estimate.
    Type: Grant
    Filed: May 8, 2001
    Date of Patent: June 1, 2004
    Assignee: Comsat Corporation
    Inventors: Yigang Fan, Prakash Chakravarthi