Back to results
US 10,651,887 B2Granted
Multiuser communication methods and devices for code division multiple access (CDMA)
AssigneeXi'an Zhongxing New Software Co., Ltd.
InventorsZhifeng Yuan, Weimin Li
Life of this patent
Estimating the term…
Abstract
Provided are multiuser communication methods and devices for Code Division Multiple Access (CDMA). N modulated symbols which are obtained by modulating a code block coded by a channel coder are acquired, where N is a positive integer more than or equal to 2. The N modulated symbols are spread according to N spread sequences with a specified length, and there may be at least two different spread sequences in the N spread sequences with the specified length. The spread modulated symbols are transmitted.
Claims21
A multiuser communication method for Code Division Multiple Access (CDMA), applied to a transmitter, the method comprising:
- acquiring N modulated symbols which are obtained by modulating a code block coded by a channel coder, where N is a positive integer more than or equal to 2;
- spreading the N modulated symbols according to N spread sequences with a specified length, wherein there are at least two different spread sequences in the N spread sequences with the specified length, the N spread sequences comprise:
- complex sequences;
- and
- transmitting the spread modulated symbols;
- wherein the complex sequences are determined in the following manner:
- generating a first real sequence with a length R according to a first Pseudo-Noise (PN) sequence generator, and generating a second real sequence with the length R according to a second PN sequence generator, where R=N×L, and L is a value of the specified length;
- determining an ith element of the first real sequence as a real part of a complex sequence, determining an ith element of the second real sequence as an imaginary part of the complex sequence, and determining a complex number comprising the real part and the imaginary part as an ith complex element of the complex sequence, where i=1,2,3 . . . , R;
- and sequentially arranging R obtained complex elements to form the complex sequence with the length R, and equally dividing the complex sequence with the length R into N complex sequences with the specified length.
6 more elements
A multiuser communication device for Code Division Multiple Access (CDMA), applied to a transmitter and comprising a hardware processor arranged to execute program modules comprising:
- a first acquisition module, arranged to acquire N modulated symbols which are obtained by modulating a code block coded by a channel coder, where N is a positive integer more than or equal to 2;
- a spreading module, arranged to spread the N modulated symbols according to N spread sequences with a specified length, wherein there are at least two different spread sequences in the N spread sequences with the specified length, the N spread sequences comprise:
- complex sequences;
- and
- a transmitting module, arranged to transmit the spread modulated symbols;
- wherein the hardware processor is arranged to execute program modules further comprising:
- a generation module, arranged to generate a first real sequence with a length R according to a first Pseudo-Noise (PN) sequence generator, and generate a second real sequence with the length R according to a second PN sequence generator, where R=N×L, and L is a value of the specified length;
- a determination module, arranged to determine an ith element of the first real sequence as a real part of a complex sequence, determine an ith element of the second real sequence as an imaginary part of the complex sequence, and determine a complex number comprising the real part and the imaginary part as an ith complex element of the complex sequence, where i=1,2,3 . . . , R;
- and
- a forming module, arranged to sequentially arrange R obtained complex elements to form the complex sequence with the length R, and equally divide the complex sequence with the length R into N complex sequences with the specified length.
7 more elements
A multiuser communication method for Code Division Multiple Access (CDMA), applied to a transmitter, the method comprising:
- acquiring N modulated symbols which are obtained by modulating a code block coded by a channel coder, where N is a positive integer more than or equal to 2;
- spreading the N modulated symbols according to N spread sequences with a specified length, wherein there are at least two different spread sequences in the N spread sequences with the specified length, wherein the N spread sequences comprise:
- complex sequences;
- and
- transmitting the spread modulated symbols;
- wherein the complex sequences are determined in the following manner:
- generating an integer sequence with a length R according to a Pseudo-Noise (PN) sequence generator, wherein elements of the integer sequence are from an integer set {0,1, . . . , D} or a set {1,2, . . . , D}, R=N×L, L is a value of the specified length, and D is a number of constellation points in a complex constellation diagram;
- selecting, from the complex constellation diagram, constellation points corresponding to the elements of the integer sequence with the length R according to a preset mapping rule;
- and
- determining the complex sequences according to the constellation points.
7 more elements
A multiuser communication method for Code Division Multiple Access (CDMA), applied to a transmitter, the method comprising:
- acquiring N modulated symbols which are obtained by modulating a code block coded by a channel coder, where N is a positive integer more than or equal to 2;
- spreading the N modulated symbols according to N spread sequences with a specified length, wherein there are at least two different spread sequences in the N spread sequences with the specified length, wherein the N spread sequences comprise:
- complex sequences;
- and
- transmitting the spread modulated symbols;
- wherein the complex sequences are determined in the following manner:
- generating real parts and imaginary parts of all complex elements in the complex sequences by virtue of a Pseudo-Noise (PN) sequence generator generating M-ary real numbers, or selecting real parts and imaginary parts of all complex elements in the complex sequences from an M-ary real number set according to a specified PN criterion, where M is an integer more than or equal to 2;
- and determining the complex sequences according to the selected real parts and imaginary parts of all the complex elements;
- wherein the complex sequences are further determined in the following manner:
- generating a first real sequence with a length R and a second real sequence with the length R according to the M-ary real number set, wherein both the first real sequence and the second real sequence adopt values in the M-ary real number set, where R=N×L, and L is a value of the specified length;
- determining an ith element of the first real sequence as a real part of a complex sequence, determining an ith element of the second real sequence as an imaginary part of the complex sequence, and determining a complex number comprising the real part and the imaginary part as an ith complex element of the complex sequence, where i=1,2,3 . . . , R;
- and sequentially arranging R obtained elements to form the complex sequence with the length R, and equally dividing the complex sequence with the length R into N complex sequences with the specified length.
9 more elements
A multiuser communication method for Code Division Multiple Access (CDMA), applied to a transmitter, the method comprising:
- acquiring N modulated symbols which are obtained by modulating a code block coded by a channel coder, where N is a positive integer more than or equal to 2;
- spreading the N modulated symbols according to N spread sequences with a specified length, wherein there are at least two different spread sequences in the N spread sequences with the specified length, wherein the N spread sequences comprise:
- complex sequences;
- and
- transmitting the spread modulated symbols;
- wherein the complex sequences are determined in the following manner:
- generating real parts and imaginary parts of all complex elements in the complex sequences by virtue of a Pseudo-Noise (PN) sequence generator generating M-ary real numbers, or selecting real parts and imaginary parts of all complex elements in the complex sequences from an M-ary real number set according to a specified PN criterion, where M is an integer more than or equal to 2;
- and determining the complex sequences according to the selected real parts and imaginary parts of all the complex elements;
- wherein the complex sequences are further determined in the following manner:
- generating an integer sequence with a length R, wherein values of the integer sequence are from an M×M-ary integer set, and the M×M-ary integer set is a set formed by all integers within a range [0, M×M−1] or [1, M×M];
- selecting, from the complex constellation diagram, constellation points corresponding to elements of the integer sequence with the length R according to a preset mapping rule;
- and
- determining the complex sequences according to the constellation points.
10 more elements
Dependencies are inferred from the claim text.