US5546420A

Wireless LAN

Title

Methods of and devices for enhancing communications that use spread spectrum technology by using variable code techniques

Application Number:

US19940235752

Publication Date:

13-08-1996

Family ID:

Application Date:

29-04-1994

Publication Country:

US

Priority Date:

29-04-1994

Declaring Company:

Abstract  Abstract

We have invented methods of and devices for introducing unequal error protection into spread spectrum communication systems. One embodiment of the invention addresses certain inefficiencies of the standard known as IS-95 used, for example, in some mobile direct sequence code division multiple access ("DS-CDMA") phone systems. The invention allows for increased system capacity and/or improved quality. More specifically, spread spectrum multiple access ("SSMA") coding may be combined with the concept of unequal error protection ("UEP"), resulting in an UEP SSMA coding process. IS-95, in order to make significant portions of a signal highly immune to errors, has imposed the same high degree of error immunity on less significant portions of the signal (when, in fact, a lower degree would suffice) and, thus, wastes bandwidth. The present inventions coding process (i.e., UEP SSMA) utilizes bandwidth in a closer to optimal manner than known methods.

Note:

The information in blue was extracted from the third parties (Standard Setting Organisation, Espacenet)

The information in grey was provided by the patent holder

The information in purple was extracted from the FrandAvenue

Explicitly disclosed patent:openly and comprehensibly describes all details of the invention in the patent document.

Implicitly disclosed patent:does not explicitly state certain aspects of the invention, but still allows for these to be inferred from the information provided.

Basis patent:The core patent in a family, outlining the fundamental invention from which related patents or applications originate.

Family member:related patents or applications that share a common priority or original filing.