CN102769592B - Method and device for generation of uplink reference signals of communication system - Google Patents

Abstract

The invention provides a method for generation of uplink reference signals of a communication system. The method includes the steps: generating a basic sequence with the length equal to N[SC]<RB> which is the number of subcarriers contained in a sub-band; multiplying the basic sequence by a cyclic shift factor to generate a reference sequence; mapping the reference sequence onto a corresponding uplink resource position; and multiplying the mapped reference sequence by an amplitude factor betaRS and then outputting. The invention further provides a device for generation of uplink reference signals of the communication system. Factors such as a frame structure, spectral distribution, sub-band width and equal-frequency networking of a grid system are considered comprehensively, the device is simple in structure, and system service requirements can be met while system performance can be guaranteed and complexity is lowered.

Description

A kind of generation method of the uplink reference signals for communication system and device

Technical field

The present invention relates to OFDM (OFDMA) technical field, particularly relate to a kind of generation method and device of the uplink reference signals for communication system.

Background technology

In the existing communication system using OFDMA access technology, reference signal (RS, ReferenceSignal) may be used for channel estimating, channel quality measurement, timing estimation etc.Reference signal is that transmission means, multi-access mode, shared bandwidth sum frequency spectrum resource etc. according to system is because usually designing.

LTE system is broadband system, with Resource Block (RB) for unit, devises length reference signal comparatively flexibly.In LTE system, up link devises two kinds of reference signals, demodulated reference signal (DMRS) and interception reference signal (SRS).DMRS is used for the coherent demodulation etc. of Physical Uplink Shared Channel (PUSCH) and Physical Uplink Control Channel (PUCCH); SRS is used for trying to find out channel quality.

Power network communication system is power load monitoring system, adopts multichannel orthogonal frequency division multiplexi.The spectrum distribution of this system is discrete, is made up of 40 discontinuous subbands, and each subband bandwidth is 25kHz.Subcarrier spacing is 2kHz, and each OFDM symbol is 10 subcarriers.The reference signal design scheme of existing multichannel ofdm system, such multichannel narrowband systems can not be used for, therefore, need the multichannel narrowband systems for power network communication system is such to redesign ascending pilot frequency scheme, the demand of systematic function and identical networking can be met.

Summary of the invention

The invention provides a kind of generation method and device of the uplink reference signals for communication system, the demand of systematic function and identical networking can be met.

The generation method of a kind of uplink reference signals for communication system that the embodiment of the present invention proposes, comprises the steps:

Generation length is basic sequence; for the number of sub carrier wave that subband comprises;

The cyclic shift factor is multiplied by described basic sequence, generating reference sequence;

With reference to sequence mapping on corresponding ascending resource position;

The reference sequences mapped is multiplied by amplitude factor β _rSand export.

The generating apparatus of a kind of uplink reference signals that the embodiment of the present invention proposes, comprising:

Basic sequence generation module, for generating length is basic sequence; for the number of sub carrier wave that subband comprises;

Reference sequences generation module, for being multiplied by the cyclic shift factor to described basic sequence basic sequence that generation module generates, generating reference sequence;

Mapping block, is mapped to corresponding ascending resource position for the reference sequences generated by described reference sequences generation module;

Output module, for being multiplied by amplitude factor β by the reference sequences mapped _rSand export.

As can be seen from the above technical solutions, the present invention considers the factor such as frame structure, spectrum distribution, subband bandwidth sum identical networking of electric power pool, and its structure is simple, can meet system traffic demand, can ensure again systematic function, reduces implementation complexity.

Accompanying drawing explanation

Fig. 1 is power network communication system upstream reference signal pattern schematic diagram;

Fig. 2 is the method flow diagram for a subband generation uplink reference signals in many subbands communication system in the embodiment of the present invention.

Embodiment

Fig. 1 is power network communication system upstream reference signal pattern.Each radio frames of power network communication system is made up of 5 subframes, and each subframe is made up of 9 OFDM symbol, and wherein subframe 2,3 and 4 is for transmitting uplink control information and uplink service information.Front 4 symbols of subframe 2 are Physical Uplink Control Channel (PUCCH), and rear 5 symbols are Physical Uplink Shared Channel (PUSCH).Subframe 3,4 is PUSCH.PUCCH and PUSCH is time division multiplexing.

For up link, the present invention devises a kind of uplink reference signals.PUCCH the 2nd and 3 OFDM symbol (i.e. the symbol 1 of subframe 2 and symbol 2) are the reference signals of PUCCH.The reference signal of PUSCH is positioned at the symbol 6 of subframe 2, the symbol 4 of subframe 3,4.Grid with hatching pattern in Fig. 1 represents reference signal.The reference signal of a given subscriber equipment (UE) is in occupation of the bandwidth (namely identical Resource Block (RB)) identical with PUSCH/PUCCH transfer of data.

Fig. 2 shows the method flow for a subband generation uplink reference signals in many subbands communication system, comprises the steps:

Step 201: generating length is zC sequence; for the number of sub carrier wave that subband comprises;

Step 202: the cyclic shift factor is multiplied by described ZC sequence, generating reference sequence;

Step 203: with reference to sequence mapping on corresponding ascending resource position;

Step 204: the reference sequences mapped is multiplied by amplitude factor α _rSand export.

For other each subbands, all generate uplink reference signals according to above-mentioned flow process, therefore repeat no more.

Each radio frames in power network communication system comprises 10 effective subcarriers.PUCCH and PUSCH uses identical basic sequence, and the sequence cyclic shift of two reference signals of PUCCH may be different, and the sequence cyclic shift of the reference sequences of 3 PUSCH is identical, and reference signal repeats to generate in units of radio frames.

Reference signal on a l symbol kth subcarrier is defined as r (l, k), and its generating mode is such as formula shown in (1):

$r(l,k)=e^{\mathrm{j\&alpha;}\left(l\right)k}\stackrel{\&OverBar;}{r}\left(k\right),0\&le;k<N_{\mathrm{sc}}^{\mathrm{RB}}---\left(1\right)$

R (l, k) comprises two parts, and a part is basic sequence a part is cyclic shift factor e ^{j α (l) k}.

In the embodiment of the present invention, described motif is classified as the truncated sequence of ZC (Zadoff-Chu) sequence, and length is 10.The concrete steps producing basic sequence comprise:

The radical sign q of step 301, calculating ZC sequence

$q=\left(N_{\mathrm{ID}}^{\mathrm{cell}}\mathrm{mod}{N}_{\mathrm{sc}}^{\mathrm{RB}}\right)+1---\left(2\right)$

Step 302, calculate the ZC sequence x of q root _q(m)

$x_q\left(m\right)=e^{-j\frac{\mathrm{\&pi;qm}(m+1)}{N_{\mathrm{ZC}}}}0\&le;m<N_{\mathrm{ZC}}---\left(3\right)$

Herein, N _zCit is ZC sequence length.In the present embodiment, N _zC=11.

Step 303, by described ZC sequence x _qbefore in (m) position is as basic sequence namely

$\stackrel{\&OverBar;}{r}\left(k\right)=x_q\left(k\right),0\&le;k<N_{\mathrm{sc}}^{\mathrm{RB}}---\left(4\right)$

The generation method of the above basic sequence is only the example of lifting for the object setting forth the present invention program, not in order to limit the present invention.In actual applications, other modes also can be adopted to generate basic sequence.

The PUCCH reference sequences r of distinct symbols _{pUCCH_RS}have respective cyclic shift, cyclic shift is based on community.PUCCH cyclic shift generation method comprises the steps:

Step 401, based on cell ID generate pseudo random sequence c (n).

Pseudo random sequence employing length is the Gold sequence of 31.Initial value is

Step 402, according to described pseudo random sequence c (n), calculate the cyclic shift α (l) of reference sequences of PUCCH

$\mathrm{\&alpha;}\left(l\right)=2\mathrm{\&pi;}\frac{({\mathrm{\&Sigma;}}_{i=0}^{7}c(8l+i)\&CenterDot;2^i)\mathrm{mod}{N}_{\mathrm{sc}}^{\mathrm{RB}}}{N_{\mathrm{sc}}^{\mathrm{RB}}}---\left(5\right)$

In the embodiment of the present invention, the cyclic shift of PUSCH is 0, that is,

α(l)＝0(6)

Therefore, the cyclic shift factor of PUSCH is 1.

Reference signal, from sub-carrier indices 0, is mapped on each subcarrier of reference symbol successively.

The notation index of reference signal is as shown in table 1:

Table 1

The reference sequences of PUCCH and PUSCH is multiplied by corresponding amplitude factor β _rS, export reference signal a _{l, k}.

a _l，k＝β _RSr(l，k)(7)

PUSCH reference symbol uses identical sequence.

Described amplitude factor can adjust according to the actual conditions of community.

The embodiment of the present invention also proposes a kind of generating apparatus of uplink reference signals, comprising:

Basic sequence generation module, for generating length is basic sequence; for the number of sub carrier wave that subband comprises;

Reference sequences generation module, for being multiplied by the cyclic shift factor to described basic sequence basic sequence that generation module generates, generating reference sequence;

Mapping block, is mapped to corresponding ascending resource position for the reference sequences generated by described reference sequences generation module;

Output module, for being multiplied by amplitude factor β by the reference sequences mapped _rSand export.

Preferably, described basic sequence generation module comprises:

Radical sign unit, for according to formula calculate the radical sign q of ZC sequence, wherein for Cell Identity CI;

ZC sequence units, for the radical sign q that exports according to radical sign unit and formula calculate the ZC sequence x of q root _q(m), and by described ZC sequence x _qbefore in (m) position is as basic sequence export; Wherein 0≤m < N _zC, N _zCzC sequence length,

Preferably, described reference sequences generation module comprises:

Pseudo random sequence generation unit, for generating pseudo random sequence c (n) based on cell ID; Pseudo random sequence is defined as the Gold sequence that length is 31, and its initial value is for Cell Identity CI;

Cycle shift unit, according to described pseudo random sequence c (n), the cyclic shift α (l) of generating reference sequence: wherein l is the call number of the OFDM symbol at reference sequences place;

Reference sequences generation unit, for the basic sequence exported described basic sequence generation module in correspond to the element of PUCCH and be multiplied by cyclic shift factor e ^{j α (l) k}, the reference signal r (l, k) obtained on a l symbol kth subcarrier exports afterwards; The element described basic sequence being corresponded to PUSCH directly exports.

Preferably, described mapping block comprises:

First map unit, for being mapped to the 2nd OFDM symbol of subframe 2 and the 3rd OFDM symbol of subframe 2 by the uplink reference signals corresponding to PUCCH;

Second map unit, for being mapped to the 7th OFDM symbol, the 5th OFDM symbol of subframe 3 and the 5th OFDM symbol of subframe 4 of subframe 2 by the uplink reference signals corresponding to PUSCH.

The present invention considers the factor such as frame structure, spectrum distribution, subband bandwidth sum identical networking of electric power pool, devises the PUCCH and PUSCH reference signal that are applicable to this system.Its structure is simple, can meet system traffic demand, can ensure systematic function again, can make channel estimating, Noise Variance Estimation simultaneously, and the algorithm realization of the timing offset of frequency domain is simpler, reduces implementation complexity.

The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment made, equivalent replacement, improvement etc., all should be included within the scope of protection of the invention.

Claims (7)

1., for a generation method for the uplink reference signals of communication system, it is characterized in that, comprise the steps:

Generation length is basic sequence, for the number of sub carrier wave that subband comprises; Comprise: according to formula calculate the radical sign q of ZC sequence, wherein for Cell Identity CI; According to formula calculate the ZC sequence x of q root _qm (), by described ZC sequence x _qbefore in (m) position is as basic sequence wherein 0≤m < N _zC, N _zCzC sequence length,

The cyclic shift factor is multiplied by described basic sequence, generating reference sequence;

With reference to sequence mapping on corresponding ascending resource position;

The reference sequences mapped is multiplied by amplitude factor β _rSand export.

2. method according to claim 1, is characterized in that, described uplink reference signals comprises the uplink reference signals of Physical Uplink Control Channel PUCCH;

Describedly the cyclic shift factor be multiplied by described basic sequence comprise:

Pseudo random sequence c (n) is generated based on cell ID; Pseudo random sequence is defined as the Gold sequence that length is 31, and its initial value is for Cell Identity CI;

According to described pseudo random sequence c (n), the cyclic shift α (l) of generating reference sequence:

wherein l is the call number of the OFDM symbol at reference sequences place;

Cyclic shift factor e is multiplied by described basic sequence r (k) ^{j α (l) k}, obtain the reference signal r (l, k) on a l symbol kth subcarrier of PUCCH.

3. method according to claim 1, is characterized in that, described uplink reference signals comprises the uplink reference signals of Physical Uplink Shared Channel PUSCH;

Describedly the cyclic shift factor be multiplied by described basic sequence comprise:

Cycle shift operation is not done to the element of the reference symbol corresponding to PUSCH in described basic sequence r (k).

4. method according to claim 1, is characterized in that, describedly comprises to corresponding ascending resource position with reference to sequence mapping:

The uplink reference signals corresponding to PUCCH is mapped to the 2nd OFDM symbol of subframe 2 and the 3rd OFDM symbol of subframe 2;

The uplink reference signals corresponding to PUSCH is mapped to the 7th OFDM symbol, the 5th OFDM symbol of subframe 3 and the 5th OFDM symbol of subframe 4 of subframe 2.

5. a generating apparatus for uplink reference signals, is characterized in that, comprising:

Basic sequence generation module, for generating length is basic sequence; for the number of sub carrier wave that subband comprises;

Reference sequences generation module, for being multiplied by the cyclic shift factor to described basic sequence basic sequence that generation module generates, generating reference sequence;

Mapping block, is mapped to corresponding ascending resource position for the reference sequences generated by described reference sequences generation module;

Output module, for being multiplied by amplitude factor β by the reference sequences mapped _rSand export; Described basic sequence generation module comprises:

Radical sign unit, for according to formula calculate the radical sign q of ZC sequence, wherein for Cell Identity CI;

ZC sequence units, for the radical sign q that exports according to radical sign unit and formula calculate the ZC sequence x of q root _q(m), and by described ZC sequence x _qbefore in (m) position is as basic sequence export; Wherein 0≤m < N _zC, N _zCit is ZC sequence length.

6. device according to claim 5, is characterized in that, described reference sequences generation module comprises:

Pseudo random sequence generation unit, for generating pseudo random sequence c (n) based on cell ID; Pseudo random sequence is defined as the Gold sequence that length is 31, and its initial value is for Cell Identity CI;

Cycle shift unit, according to described pseudo random sequence c (n), the cyclic shift α (l) of generating reference sequence: wherein l is the call number of the OFDM symbol at reference sequences place;

Reference sequences generation unit, for the basic sequence exported described basic sequence generation module be multiplied by cyclic shift factor e ^{j α (l) k}, the reference signal r (l, k) obtained on a l symbol kth subcarrier of PUCCH exports afterwards; The element described basic sequence being corresponded to the reference symbol of PUSCH directly exports.

7. device according to claim 5, is characterized in that, described mapping block comprises:

First map unit, for being mapped to the 2nd OFDM symbol of subframe 2 and the 3rd OFDM symbol of subframe 2 by the uplink reference signals corresponding to PUCCH;

Second map unit, for being mapped to the 7th OFDM symbol, the 5th OFDM symbol of subframe 3 and the 5th OFDM symbol of subframe 4 of subframe 2 by the uplink reference signals corresponding to PUSCH.