Method for synchronizing a receiver with a transmitter
AssigneeSiemens Aktiengesellschaft
InventorBernhard Raaf
Life of this patent
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Abstract
A first synchronization signal having a multitude of second synchronization signals, which are removed from a set of second synchronization signals that is subdivided into code sets, is transmitted by a transmitter to a receiver. According to the invention, the multitude of second synchronization signals, which are transmitted with the first synchronization signal, are specified by a code set, whereby the code sets are grouped into used and unused code sets, and whereby the set of second synchronization sequences is subdivided into code sets such that the maximum of the peak values of the cross-correlation functions of the second synchronization signals, which are specified by a used code set, with the first synchronization signal is minimal.
Claims13
A method for synchronizing a receiver with a transmitter,
- in which a first synchronization signal with a multiplicity of second synchronization signals which are taken from a set of second synchronization signals that is subdivided into code sets is transmitted from the transmitter to the receiver,
- in which the multiplicity of second synchronization signals that are transmitted with the first synchronization signal is determined by a code set,
- in which the code sets are grouped into used code sets and at least one unused code set, and
- in which the set of second synchronization signals is subdivided into code sets in such a way that the maximum in the peak values of the cross-correlation functions of the second synchronization signals, which are determined by a used code set, with the first synchronization signal is minimal.
A Method for synchronizing of a receiver with a transmitter,
- in which the transmitter transmits a first synchronization signal with a multiplicity of second synchronization signals, the multiplicity of second synchronization signals that can be transmitted jointly being determined by a grouping of second synchronization signals into code sets, and the code sets being formed in such a way that the maximum in the peak values of the cross-correlation functions of the second synchronization signals with the first synchronization signal is minimal.
A method for selecting a multiplicity of second synchronization signals that are transmitted jointly with a first synchronization signal,
- in which the multiplicity of second synchronization signals are selected from a set of second synchronization signals,
- in which the set of second synchronization signals is subdivided into code sets,
- in which the code sets are grouped into used code sets and at least one unused code set,
- in which the set of second synchronization sequences is subdivided into code sets in such a way that the maximum in the peak values of the cross-correlation functions of the second synchronization signals, which are contained in a used code set, with the first synchronization signal is minimal.
The Method as claimed in one of the preceding claims for use in the TDD mode of a UMTS system.
The method as claimed in one of the preceding claims, in which all the synchronization signals of the set of second synchronization signals are used for synchronization in the FDD mode of the UMTS system.
The method as claimed in one of the preceding claims, in which the first synchronization signal is a hierarchic sequence, and in which the second synchronization signals can be obtained in each case by the positional multiplication of the first synchronization signal by in each case one row of a Hadamard matrix.
The method as claimed in one of the preceding claims, in which the synchronization signals can be formed in the following way:
- the first synchronization signal Cp is determined by the following relationship:
- Cp=<y(0),y(1),y(2), . . . , y(255)>, wherein it holds that:
- y=(1+j)×<a,a,a,−a,−a,a,−a,−a,a,a,a,−a,a, a,a,a>, wherin it holds that:
- −a=<x1, x2, x3, . . . , x16>=<1, 1, 1, 1, 1, 1, −1, −1, 1, −1, 1, −1, 1, −1, −1, 1>;
- 16 second synchronization signals {C0, . . . , C15) are determined by the following relationship:
- Ci=CSCH, i, i=0, . . . , 15, wherein it holds that:
- CSCH, i=(1+j)×<hm(0)×z(0), hm(1)×z(1), hm(2)×z(2), . . . , hm) (255)×z(255)>, wherein it holds that:
- m=(16×i)
- the nth Hadamard sequence hn is a series of a Matrix H8, which can be formed recursively by means of the following relationship:
- 2 H 0 = ( 1 ) H k = ( H k - 1 H k - 1 H k - 1 - H k - 1 ) , k ≥ 1
- , the numbering beginning at the top with zero, n=0, 1, 2, . . . , 255;
- hm(i) and z(i) denote the ith symbol of the sequence hm and z, respectively, wherein i=0, 1, 2, . . . , 255 and i=0 corresponds to the symbol at far left.
The method as claimed in one of the preceding claims, in which the used code sets are defined as follows:
- Code set 1:
- SSC1, SSC3, SSC5;
- Code set 2:
- SSC10, SSC13, SSC14;
- Code set 3:
- SSC0, SSC6, SSC12;
- Code set 4:
- SSC4, SSC8, SSC15.
The method as claimed in one of the preceding claims, in which the temporal position of the first synchronization sequence and the temporal position of the multiplicity of second synchronization sequences are determined at the receiving end by means of correlation calculations.
The method as claimed in one of the preceding claims in which the first synchronization sequence is used at the receiving end for time slot synchronization, and the multiplicity of second synchronization sequences is used for frame synchronization.
The method as claimed in one of the preceding claims, in which in the case of the minimization criterion the maximum in the peak values of the cross-correlation functions of the second synchronization signals, which are determined by a used code set, is also taken into account with the aid of the first synchronization signal in conjunction with at least one frequency error.
The method as claimed in one of the preceding claims, in which in the case of a plurality of alternatives with the same maximum in the peak values of the the cross-correlation functions of the second synchronization signals, which are determined by a used code set, with the first synchronization signal, the RMS value of this cross-correlation function is minimized as subordinate criterion.
The method as claimed in one of the preceding claims, in which the maximum in the peak values of the cross-correlation functions is minimized by modulated superpositions of second synchronization signals, which are determined by a used code set, with the first synchronization signal.
Dependencies are inferred from the claim text.