US6091760A — Non-recursively generated orthogonal PN codes for…

Claim 1

Independent Claim 78 words

A non-recursive method for constructing balanced PN code sets for use in a code division, multiple access (CDMA) communication system, comprising steps of: applying a constrained permutation to a G x G ±1 valued matrix to form a modulation matrix M(G); and using the modulation matrix M(G) to create a set of available PN codes for a first cell by modulating R unique nxn permuted code sets, c.sup.(1) (n) to c.sup.(R) (n), by successive scalar elements of M(G).

Claim 2

Dependent Claim 78 words

A non-recursive method for constructing balanced PN code sets for use in a code division, multiple access (CDMA) communication system, comprising steps of: applying a constrained permutation to a G x G ±1 valued matrix to form a modulation matrix M(G); and using the modulation matrix M(G) to create a set of available PN codes for a first cell by modulating R unique nxn permuted code sets, c.sup.(1) (n) to c.sup.(R) (n), by successive scalar elements of M(G).

Claim 3

Dependent Claim 25 words

A method as in claim 1, wherein the step of using the modulation matrix M(G) comprises a step of operating a scalar times matrix multiplier.

Claim 4

Dependent Claim 68 words

A method as in claim 1, wherein the step of using the modulation matrix M(G) uses the entire M(G) modulation matrix to create a matrix ##EQU8## where D.sup.(1) is a Gn x RGn matrix, having elements D 1 1 , . . . , D 1 i . . . D 1 G , containing Gn PN codes having length RGn chips for use in the first cell.

Claim 5

Dependent Claim 41 words

A method as in claim 3, wherein another Gn x RGn matrix, D.sup.(2), is created for a second cell using permuted PN codes c.sup.(R+1) (n), c.sup.(R+2) (n), . . . , c.sup.(2R) (n), and the same or another modulation matrix M(G).

Claim 6

Dependent Claim 21 words

A method as in claim 1, wherein said CDMA communication system is one of a multirate synchronous or quasi-synchronous CDMA system.

Claim 7

Dependent Claim 42 words

A method as in claim 1, wherein said step of applying a constrained permutation comprises a step of selectively permuting columns within column pairs, column pairs within column quads, column quads within column octals, and higher levels if present, in any order.

Claim 8

Dependent Claim 83 words

A non-recursive method for constructing balanced PN code sets for use in a code division, multiple access (CDMA) communication system, comprising steps of: permuting the columns of a first orthogonal Hadamard matrix; using the permuted Hadamard matrix to modulate second permuted orthogonal Hadamard matrices to create balanced PN code sets capable of supporting multirate CDMA operation; and assigning, as a function of transmission rate, at least one PN code from the balanced PN code sets to a user of the CDMA communication system.

Claim 9

Dependent Claim 83 words

A non-recursive method for constructing balanced PN code sets for use in a code division, multiple access (CDMA) communication system, comprising steps of: permuting the columns of a first orthogonal Hadamard matrix; using the permuted Hadamard matrix to modulate second permuted orthogonal Hadamard matrices to create balanced PN code sets capable of supporting multirate CDMA operation; and assigning, as a function of transmission rate, at least one PN code from the balanced PN code sets to a user of the CDMA communication system.

Claim 10

Dependent Claim 23 words

A method as in claim 7, wherein said CDMA communication system is at least one of a multirate synchronous or quasi-synchronous CDMA system.

Claim 11

Independent Claim 61 words

A method for improving the spectral properties of a PN codeset for use in a synchronous or quasi-synchronous CDMA communications system, comprising steps of: providing a PN codeset matrix; reordering the columns of the PN codeset matrix by exchanging columns in accordance with a reordering code to form a reordered matrix; and modulating the reordered matrix with a permuted modulation matrix.

Claim 12

Independent Claim 61 words

A method for improving the spectral properties of a PN codeset for use in a synchronous or quasi-synchronous CDMA communications system, comprising steps of: providing a PN codeset matrix; reordering the columns of the PN codeset matrix by exchanging columns in accordance with a reordering code to form a reordered matrix; and modulating the reordered matrix with a permuted modulation matrix.

Claim 13

Dependent Claim 25 words

A method as in claim 9, wherein the step of reordering further comprises a step of inverting at least one codeword of the reordered matrix.

Claim 14

Dependent Claim 97 words

A synchronous or quasi-synchronous CDMA communications system, comprising: a radio base unit capable of bidirectional wireless multirate communications with a plurality of subscriber units; and a controller for reordering columns of a Hadamard codeset matrix by exchanging columns in accordance with a predetermined reordering code to produce a reordered pseudonoise (PN) codeset having improved spectral properties, and for then modulating the reordered matrix with a permuted modulation matrix to generate usable PN codes and assigning individual ones of the usable PN codes to requesting ones of the subscriber units as a function of subscriber unit data rate.

Claim 15

Dependent Claim 97 words

A synchronous or quasi-synchronous CDMA communications system, comprising: a radio base unit capable of bidirectional wireless multirate communications with a plurality of subscriber units; and a controller for reordering columns of a Hadamard codeset matrix by exchanging columns in accordance with a predetermined reordering code to produce a reordered pseudonoise (PN) codeset having improved spectral properties, and for then modulating the reordered matrix with a permuted modulation matrix to generate usable PN codes and assigning individual ones of the usable PN codes to requesting ones of the subscriber units as a function of subscriber unit data rate.

Claim 16

Dependent Claim 22 words

A system as in claim 11, wherein said controller further comprises means for inverting at least one codeword of the reordered matrix.

Claim 17

Dependent Claim 73 words

A non-recursive method for improving the spectral properties of PN codes derived from a Hadamard matrix for use in a synchronous or quasi-synchronous CDMA communications system, comprising steps of: providing a Hadamard matrix; reordering columns of the Hadamard matrix in accordance with a reordering code to generate a reordered Hadamard matrix; and multiplying elements of the reordered Hadamard matrix by a multiplication matrix obtained from a constrained permutation of a GxG Hadamard matrix.

Claim 18

Dependent Claim 73 words

A non-recursive method for improving the spectral properties of PN codes derived from a Hadamard matrix for use in a synchronous or quasi-synchronous CDMA communications system, comprising steps of: providing a Hadamard matrix; reordering columns of the Hadamard matrix in accordance with a reordering code to generate a reordered Hadamard matrix; and multiplying elements of the reordered Hadamard matrix by a multiplication matrix obtained from a constrained permutation of a GxG Hadamard matrix.

Claim 19

Dependent Claim 25 words

A method as in claim 13, and comprising an initial step of generating the reordering code using one of a random or pseudo-random number generator.

Claim 20

Dependent Claim 34 words

A method as in claim 13, wherein the step of reordering further comprises steps of defining an inversion pattern, and inverting at least one codeword of the reordered Hadamard matrix using the inversion pattern.

Claim 21

Dependent Claim 34 words

A method as in claim 14, wherein the step of inverting includes a step of multiplying each element in a row of the reordered Hadamard matrix by a corresponding element of the inversion pattern.

Claim 22

Dependent Claim 32 words

A method as in claim 14, wherein the reordered Hadamard matrix is an i row by j column matrix, and wherein the inversion pattern is an i row by one column matrix.

Claim 23

Independent Claim 215 words

A method for assigning balanced spreading codes for use in a synchronous or quasi-synchronous code division, multiple access (CDMA) communication system, comprising steps of: non-recursively generating spreading codes by applying a constrained permutation to a GxG ±1 valued matrix to form a modulation matrix M(G) by selectively permuting columns within column pairs, column pairs within column quads, column quads within column octals, and higher levels if present, in any order; and using the modulation matrix M(G) to create a set of available spreading codes for a first cell by modulating R unique nxn permuted code sets, c.sup.(1) (n) to c.sup.(R) (n), by successive scalar elements of M(G), the available spreading codes being found in a matrix ##EQU9## where D.sup.(1) is a Gn x RGn matrix, having elements D 1 1 , . . . , D 1 i . . . D 1 G ; and then assigning spreading codes for highest data rate users from only the first n rows of D.sup.(1), assigning spreading codes for second highest data rate users from only the first 2n rows of D.sup.(1) assigning spreading codes for third highest data rate users from only the first 4n rows of D.sup.(1), and so forth, thereby avoiding an assignment of perfectly correlated or anti-correlated spreading codes to two users simultaneously.

Claim 24

Independent Claim 215 words

A method for assigning balanced spreading codes for use in a synchronous or quasi-synchronous code division, multiple access (CDMA) communication system, comprising steps of: non-recursively generating spreading codes by applying a constrained permutation to a GxG ±1 valued matrix to form a modulation matrix M(G) by selectively permuting columns within column pairs, column pairs within column quads, column quads within column octals, and higher levels if present, in any order; and using the modulation matrix M(G) to create a set of available spreading codes for a first cell by modulating R unique nxn permuted code sets, c.sup.(1) (n) to c.sup.(R) (n), by successive scalar elements of M(G), the available spreading codes being found in a matrix ##EQU9## where D.sup.(1) is a Gn x RGn matrix, having elements D 1 1 , . . . , D 1 i . . . D 1 G ; and then assigning spreading codes for highest data rate users from only the first n rows of D.sup.(1), assigning spreading codes for second highest data rate users from only the first 2n rows of D.sup.(1) assigning spreading codes for third highest data rate users from only the first 4n rows of D.sup.(1), and so forth, thereby avoiding an assignment of perfectly correlated or anti-correlated spreading codes to two users simultaneously.

Claim 25

Dependent Claim 25 words

A method as in claim 18, wherein the step of using the modulation matrix M(G) comprises a step of operating a scalar times matrix multiplier.

Claim 26

Dependent Claim 41 words

A method as in claim 18, wherein another Gn x RGn matrix, D.sup.(2), is created for a second cell using permuted spreading codes c.sup.(R+1) (n), c.sup.(R+2) (n), . . . , c.sup.(2R) (n), and the same or another modulation matrix M(G).

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2003-07-18	2004-01-17	2004-07-18	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2007-07-18	2008-01-17	2008-07-18	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2011-07-18	2012-01-17	2012-07-18	$7700.00	Window Closed / Lapsed

Non-recursively generated orthogonal PN codes for variable rate CDMA

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