Method and apparatus for code division multiple access communication with increased capacity through self-noise reduction
AssigneeSirius Communications N.V.
InventorsJan Mennekens, Carl Mertens, Lieven Philips, Jurgen Vandermot, Jan Vanhoof
Life of this patent
Estimating the term…
Abstract
A method of generating a waveform with a plurality of orthogonal PN codes for use in a communications network utilizing quasi-synchronous code division multiple access. The orthogonal PN codes modulate multiple data streams together with a non-orthogonal PN code having desirable auto-correlation properties. The result is a complex signal with time-aligned PN codes.
Claims4
A method to generate a waveform with a plurality of orthogonal PN codes, to modulate a plurality of data streams, together with a non-orthogonal PN-code, having good auto-correlation properties, comprising the steps of:
- Taking a plurality of orthogonal codes that are used to spread a plurality of data streams;
- combining each of said spread data streams with in-phase BPSK modulations, and performing an addition, after optional gain control of each spread stream to obtain first signals;
- Defining a PN-code with good auto-correlation properties, and combining said code with BPSK modulation, which is orthogonal (90 degrees out-of-phase) with said BPSK modulations to obtain second signals;
- Combining said first and second signals as a complex signal with time-aligned PN-codes.
Dependencies are inferred from the claim text.