Resources Contact Us Home
Multicode direct sequence spread spectrum

Image Number 14 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
Method for fabricating solar cell
Integrated emergency medical database system
IR(voltage) drop analysis in integrated circuit timing
Housekeeping cart
Architectural panel with millet and grass
Method for preparing a .beta.-SiAlON phosphor
Single mode optical fiber with improved bend performance
  Randomly Featured Patents
Sports lighting luminaire having a broken glass safety shutdown circuit
Drop-on-demand ink jet printing with controlled fluid flow during drop ejection
Process for continuously treating thermoplastic yarns
Apparatus and method for projecting field devices of a technical system
Precipitation polymerization process for producing an oil adsorbent polymer capable of entrapping solid particles and liquids and the product thereof
Motion adaptive video processing system
Method and apparatus for increasing heat transfer efficiency
Heteroaryl carboxamides
Vertical movement closing device for various containers
Collapsible hitch mounted cargo carrier