 Independent remote computer maintenance device |
| It is an object of the present invention to provide an independent computing device for diagnosing ... |
|
| Method, system, and program for diagnosing a computer in a network system |
| OF THE PREFERRED EMBODIMENTS In the following description, reference is made to the accompanying ... |
|
| Methods for quantitative analysis by tandem mass spectrometry |
| Embodiments of the present invention provide methods for deconvoluting contributions of a plurality ... |
|
| Method for optimizing test development for digital circuits |
| The present invention provides test patterns to detect timing related failures in large digital ICs,... |
|
| Switchable pull-ups and pull-downs for IDDQ testing of integrated circuits |
| OF THE INVENTION The present invention provides a switchable pull-up circuit particularly well-... |
|
| Testing of digital-to-analog converters |
| In general, a technique for testing digital-to-analog converters includes providing a set of ... |
|
| Method and apparatus for failure detection utilizing functional test vectors and scan mode |
| OF THE INVENTION A method and software for failure detection of logic nodes within an integrated ... |
|
|
Communications system handoff operation combining turbo coding and soft handoff techniques
| Details |
Inventors: Yi, Byung Kwan;
Assignee: Orbital Sciences Corporation (Dulles, VA)
Primary Examiner: Marcelo; Melvin
Assistant Examiner:
Attorney, Agent or Firm: McDermott, Will & Emery
Communication systems, including, for example, cell-based mobile communication systems, multiple satellite communication systems, or multibeam satellite systems, require reliable handoff methods between cell-to-cell, beam-to-beam, or satellite-to-satellite respectively. Recent measurement of a CDMA cellular system indicates that the system is in handoff about 30% to 50% of an average call period. Therefore, system reliability during handoff is one of the major system performance parameters and eventually becomes a factor in the overall system capacity. The present invention advantageously relates to novel and improved techniques for handoff in cellular communications, multibeam and multisatellite systems. The present invention combines the soft handoff mechanism wvith a code diversity combining technique (i.e., combining signals from multiple sources), a packet combining technique (i.e., combining multiple signals), and an iterative decoding algorithm (e.g., Turbo Coding). |
|
DETAILED DESCRIPTION What is claimed is: 1.
A mobile communication system, comprising: a source of digital data, for communication to or from a predetermined one of a plurality of mobile stations; a first constituent encoder, coupled to the source, for encoding the digital data into a first code sequence; an intierleaver, coupled to the source, for interleaving the digital data; a second constituent encoder, coupled to the interleaver, for encoding the interleaved digital data into a second code sequence; a first code puncturer, coupled to the first and second constituent encoders, for selectively replacing data in the first code sequence with selected data from the second code sequence to form a first punctured code sequence; a second code puncturer, coupled to the first and second constituent encoders, for selectively replacing data in the second code sequence with selected data from the first code sequence to form a second punctured code sequence; first and second transmitters for transmission of information on first and second logical channels assigned to the predetermined mobile station; and a control coupled to the first and second transmitters, wherein during a handoff operation, the control causes the first transmitter to broadcast the first channel carrying the digital data together with the first punctured code sequence, and concurrently causes the second transmitter to broadcast the second channel carrying the interleaved digital data together with the second punctured code sequence.
2.
A mobile communication system as in claim 1, further comprising a receiver, the receiver comprising: at least one antenna for receiving signals from the transmitters; processing circuitry coupled to the at least one antenna for recovering data from the first logical channel during handoff and for recovering data from the second logical channel during handoff; and an intelligent decoder, coupled to the processing circuitry, for decoding signals from the first and second logical channels during handoff, to recover an accurate representation of the digital data
|
| Related patents |
|
|
System for coding system
OF THE PREFERRED EMBODIMENT Having summarized the present invention, reference will now be made in detail to the description of the invention as illustrated in the ...
|
|
|
Process for transmitting information bits with error correction coding, coder and decoder for the implementation of this process
The invention therefore proposes, in a process of the type indicated in the introduction, that a set of Y bits respectively having Y determined positions in the second ...
|
|
|
Process for transmitting information bits with error correction coding and decoder for the implementation of this process
The invention therefore proposes in a process of the type indicated in the introduction, that the first binary matrix comprises, in addition to the information bits, a ...
|
|
|
Punctured serial concatenated convolutional coding system and method for low-earth-orbit satellite data communication
In accordance with this invention, a coding system ideally suited for use in a low-Earth-orbit (LEO) satellite data communication network is provided. Data to be ...
|
|
|
Method and system for fast maximum a posteriori decoding
In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular circuits, circuit components, ...
|
|
|
Turbo decoder control for use with a programmable interleaver, variable block length, and multiple code rates
A control for a turbo decoder utilizing a MAP decoding algorithm comprises an address generator for addressing systematic data symbols, parity data symbols, and ...
|
|
|
Method and apparatus for turbo decoding of trellis coded modulated signal transmissions
Briefly, the present invention implements an iterative decoding system within a Trellis Coded Modulation communications environment. The improved Trellis-coded ...
|
|
|
Semiconductor integrated circuit boundary scan test with multiplexed node selection
The object of the present invention is therefore to provide a semiconductor integrated circuit having a test circuit built therein to facilitate the board test of ...
|
|
|
Testing the integrity of an electrical connection to a device using an onboard controllable signal source
OF THE INVENTION The present invention is directed to systems and a method for testing the integrity of an electrical connection mounted on a circuit assembly using an ...
|
|
|
Apparatus for I/O leakage self-test in an integrated circuit
According to one embodiment, an integrated circuit is disclosed that includes a first input/output (I/O) circuit and a leakage detection circuit coupled to the first I/O ...
|
|
|
Fault Detection 
