Resources Contact Us Home
Multicode direct sequence spread spectrum

Image Number 16 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
Solid-state imaging device, method for manufacturing solid-state imaging device, and electronic apparatus
Method, apparatus and article for detection of transponder tagged objects, for example during surgery
Front exterior of an automotive tail lamp
Method for conformal plasma immersed ion implantation assisted by atomic layer deposition
Semiconductor device and method of adjusting characteristic thereof
Non-volatile flash-RAM memory with magnetic memory
Substituted di-arylhydantoin and di-arylthiohydantoin compounds and methods of use thereof
  Randomly Featured Patents
Rubber sheet jointing apparatus and method
Conversion of high boiling liquid organic materials to lower boiling materials
System, charging device, and method of supplying current to a power storage device
Esterification reaction products
Portable digital photographing system combining position navigation information and image information
Controlled torque air motor
Pump including an insertion valve sleeve having at least one orifice
MOS Power-on reset circuit
Fuel tank provided with air guide structure of straddle-type vehicle
Information processing apparatus, device operation setting method and recording medium