Wireless direct sequence spread spectrum digital cellular telephone system

• US 5,734,639 A
• Filed: 05/08/1996
• Issued: 03/31/1998
• Est. Priority Date: 06/07/1994
• Status: Expired due to Term

• Current Assignee: Lctl Wireless Investment LLC (Intellectual Ventures LLC)
• Original Assignee: Stanford Telecommunications, Inc. (Nokia Corporation)
• Inventors: Bustamante, Herman, Natali, Francis, Magill, David T.
• Primary Examiner(s): HSU, ALPUS
• Application Number:
  US08/646,387
• Time in Patent Office: 692 Days
• Field of Search: 375/200, 375/205, 375/219, 375/220, 375/344, 375/356, 375/371, 375/373, 375/378, 375/208, 455/33.1, 455/33.2, 455/35.1, 455/53.1, 455/54.1, 455/71, 455/76, 455/88, 455/89, 455/205, 455/208, 455/255, 455/257, 455/258, 455/259, 455/260, 455/265, 455/267, 379/58, 379/59, 379/60, 379/61, 331/47.55, 370/206, 370/208, 370/335, 370/342, 370/350, 370/515, 370/516, 370/518
• US Class Current: 370/208
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity
• CPC Class Codes: H04B 7/216 Code division or spread-spectrum multiple access [CDMA, SSMA]
• CPC Class Codes: H04B 7/2628 using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA] H04B7/2618 takes precedence
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity
• CPC Class Codes: H04W 84/14 WLL [Wireless Local Loop]; RLL [Radio Local Loop]

Abstract

An exceptionally efficient operation is achieved through the use of orthogonal code divisional multiple access radio communication between a base station and a plurality of user handsets. Each user handset is provided with a local oscillator. The base station transmits a reference pilot/sounding signal which is received at the user handsets and the local oscillators at the user handsets are phase locked to the reference pilot/sounding signal.

Claims

1. A method of achieving orthogonal code division multiple access (CDMA) wireless telephone communications between a base station and a plurality of user handsets wherein a set of orthogonal functions are overlaid with a pseudonoise (PN) sequence for an information signal, with each orthogonal function carrying the information signal of a single user handset, respectively, wherein:

each said user handset having a local oscillator, comprising transmitting a reference pilot/sounding signal from said base station, receiving said reference pilot/sounding signal at said user handsets, and phase-locking each said handset local oscillator to said reference pilot/sounding signal.