Resources Contact Us Home
Multicode direct sequence spread spectrum

Image Number 19 for United States Patent #RE37802.

In this patent, we present MultiCode Direct Sequence Spread Spectrum (MC-DSSS) which is a modulation scheme that assigns up to N DSSS codes to an individual user where N is the number of chips per DSSS code. When viewed as DSSS, MC-DSSS requires up to N correlators (or equivalently up to N Matched Filters) at the receiver with a complexity of the order of N.sup.2 operations. In addition, a non ideal communication channel can cause InterCode Interference (ICI), i.e., interference between the N DSSS codes. In this patent, we introduce new DSSS codes, which we refer to as the "MC" codes. Such codes allow the information in a MC-DSSS signal to be decoded in a sequence of low complexity parallel operations which reduce the ICI. In addition to low complexity decoding and reduced ICI. MC-DSSS using the MC codes has the following advantages: (1) it does not require the stringent synchronization DSSS requires, (2) it does not require the stringent carrier recovery DSSS requires and (3) it is spectrally efficient.

  Recently Added Patents
Storing compression units in relational tables
Fluid treatment arrangements with sets of fluid treatment elements and methods for making and using them
CO2 estimator module
Biosurfactant compounds produced by Aureobasidium pullulans
Method and apparatus for estimation of channel temporal correlation and MIMO mode selection in LTE system
Method for clearing native oxide
Image processing device and processing method thereof
  Randomly Featured Patents
Hydraulic accumulator
Measuring of earth fault current
Polyolefin connectors
UV excitable energy transfer reagents
Multiple-lights-combining illumination device and projection-type display apparatus using the same
Method of routing an international call to a foreign mobile subscriber
Heating system for vehicles
Apparatus for connecting a cover band to guide blading of a turbomachine
Recording and playback apparatus using harddrive for ripping digital audio data
Thermal transfer plate and integrated circuit chip or other electrical component assemblies including such plate