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
Suspension with flexure having laminated structure and bonding pads on opposing surfaces thereof, and head gimbal assembly and disk drive unit with the same
Method and composition for attracting arthropods by volatizing an acid
Method and apparatus for verifiable generation of public keys
Noise suppression in speech signals
Method and system for providing an intelligent visual scrollbar position indicator
System and method for a TCP mapper
Method for manufacturing and reoxidizing a TiN/Ta.sub.2O.sub.5/TiN capacitor
  Randomly Featured Patents
Apparatus and method for reducing power consumption by peripheral devices after downloading a program therefrom
Antisebum and antioxidant compositions containing guguliped and alcoholic fraction thereof
Segmented briquetting roll
Method for evaluating characteristic values of piezo-mechanical systems
Photodiode array and method for establishing a link between a first semiconductor element and a second semiconductor element
Virtual cache registers with selectable width for accommodating different precision data formats
Mask for door hinges
Image processing apparatus and image processing method
3-Substituted-6.beta.-(amino- and acylamino)-7-oxo-1,3-diazabicyclo[3.2.0]- h
Superconducting fault current-limiter with variable shunt impedance