EP1826872A1 - Verfahren zur Optimierung des Abstandes zwischen Empfangsantennen eines Arrays als Gegenmassnahme gegen Interferenz und Fading in zellularen Systemen - Google Patents

Verfahren zur Optimierung des Abstandes zwischen Empfangsantennen eines Arrays als Gegenmassnahme gegen Interferenz und Fading in zellularen Systemen Download PDF

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Publication number
EP1826872A1
EP1826872A1 EP06425093A EP06425093A EP1826872A1 EP 1826872 A1 EP1826872 A1 EP 1826872A1 EP 06425093 A EP06425093 A EP 06425093A EP 06425093 A EP06425093 A EP 06425093A EP 1826872 A1 EP1826872 A1 EP 1826872A1
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EP
European Patent Office
Prior art keywords
barycentric
spacing
opt
interfering
interferers
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Application number
EP06425093A
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English (en)
French (fr)
Inventor
Claudio Santacesaria
Luigi Sampietro
Umberto Spagnolini
Monica Nicoli
Osvaldo Simeone
Stefano Savazzi
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Siemens SpA
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Siemens SpA
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Publication date
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Priority to EP06425093A priority Critical patent/EP1826872A1/de
Priority to PCT/EP2007/001238 priority patent/WO2007093384A1/en
Priority to CNA2007101379975A priority patent/CN101083498A/zh
Publication of EP1826872A1 publication Critical patent/EP1826872A1/de
Withdrawn legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/12—Supports; Mounting means
    • H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
    • H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
    • H01Q1/241—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
    • H01Q1/246—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for base stations
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00—Antenna arrays or systems
    • H01Q21/06—Arrays of individually energised antenna units similarly polarised and spaced apart
    • H01Q21/08—Arrays of individually energised antenna units similarly polarised and spaced apart the units being spaced along or adjacent to a rectilinear path
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00—Antenna arrays or systems
    • H01Q21/06—Arrays of individually energised antenna units similarly polarised and spaced apart
    • H01Q21/22—Antenna units of the array energised non-uniformly in amplitude or phase, e.g. tapered array or binomial array

Definitions

  • the present invention relates to the field of wireless telecommunications networks, and more precisely to a method for optimizing the spacing between receiving antennas of an array usable for counteracting both interference and fading in cellular systems.
  • the invention is suitable to be employed in the Base Station receivers of multi-cell wireless systems based on frequency reuse in adjacent cells and, if needed, employing the SDMA technique in the same cell.
  • the invention could find particular application in cellular systems based on different types of radio access, either narrowband or broadband, such GSM, UMTS, WiMAX IEEE 802.16-2004, WiMAX IEEE 802.16e, HiperMAN ETSI. TS 102 177, etc.
  • the invention could also be applied, with obvious modifications anyway covered by the claims, to receivers belonging to Subscriber Stations and/or point-to-point links.
  • the multipath fading together with co-channel interference from subscriber stations in the same or adjacent cells are the major sources of SINR degradation at the output of the receivers.
  • the multi-cell interference is accounted by a spatial covariance matrix (or noise power) that is assumed as constant, and applying a spatial filter on the received signals (and a pre-filter at the transmitter whenever available) to improve the SINR at the output.
  • SINR Multiple antennas
  • SIMO/MIMO Multiple antennas
  • diversity and beamforming are two different strategies typically adopted depending on the specific impairment, either fading or interference, that has to be contrasted.
  • There are some freedoms in the design of the arrays so as in the design of the reception signal processing.
  • the spacing between adjacent antennas is not optimized to the channel/interference parameters and to the receiver scheme.
  • Small spacing is typically adopted in LOS environments where beamforming is more effective in filtering the interference.
  • NLOS applications call for diversity-oriented approaches. Still, most of the environments are characterized by mixed LOS/NLOS conditions and they need an optimized spacing whose value is between the two extreme cases mentioned above.
  • a spacing larger than ⁇ /2 introduces a certain degree of angular equivocation in the directivity function of the ULA, aimed to induce the latter to see the interferers (all or a certain number depending on the degree of freedom of the directivity function) as grouped together along an unique apparent direction.
  • the minimization of the spread of the wave numbers results in the maximization of the array interference suppression capability. This should allow to release some degrees of freedom of the directivity function, so that a corresponding number of zeroes could be placed at the angular positions they mostly were needed, for example in correspondence of the common direction of the interferers for a deeper attenuation.
  • the optimal theoretical spacing ⁇ opt is calculable in known way under the following restrictive hypotheses: a) null angular spread on the channel; b) interfering terminals are located in fixed positions with main DOAs symmetric with respect to the broadside direction; c) all terminals transmit with maximum power.
  • Object of the invention is that of obtaining the optimum spacing in closed mathematical form when real radio paths are taken into account without needing of demanding simulations, limitedly to an uniform linear array under some specific assumptions on the structure of the cellular planning and the interference .
  • the invention provides a method for optimizing the spacing between the antennas of a receiving uniform array usable in a receiving station, either fixed or mobile, of a cellular communication system, as disclosed in claim 1.
  • the spacing so calculated is automatically optimized to the channel/interference parameters, and could be larger than the canonical ⁇ /2 for trading between large spacing to take advantage of diversity and small spacing to have accurate interference rejection capability. This is suitable for either LOS, NLOS or mixed LOS/NLOS propagation environments.
  • the only pre-condition for the method is the symmetry of the main interfering paths with respect to the broadside direction of the array, to say, we are considering a planning by which the normal to the line crossing all antennas of the array is crossed by an interfering cell and the other interfering cells are symmetrically disposed with respect to the broadside direction.
  • This is a reasonably assumption valid for all the most popular planning, e.g. square, hexagonal, etc.
  • the interferer should be placed at the centre o the cell, in such a case the motion of the transmitter should not be accounted.
  • the method of the invention overcomes this limitation by considering the motion of the interfering user as it happen in correspondence of the points of a grid used to spread the multipath over the complete cell.
  • the multipath generated by the i th interferer station ideally collapses in a single path characterized by a barycentric DOA ⁇ i B and a barycentric received power P i B .
  • the i th barycentric DOA is calculated from the power-angle profile of the channel between the interfering station located in the i th cell and the receiving station located in the cell of interest, when the spatial location of the interfering station is randomly distributed within its cell.
  • the i th barycentric DOA is calculated by executing a weighted average extended to the N p ⁇ S directions of arrival of the N p paths by the S points of a grid indicative of the positions spanned by the i th interfering station inside its cell, weighting each DOA by the power received on that path.
  • the successive step is that to find a an angular separation between the interferers to be introduced into the theoretical expression to get the maximum equivocation, and hence the optimal spacing ⁇ opt .
  • this is done calculating a weighted average barycentric DOA separation ⁇ B and introducing it into the theoretical expression of the maximum equivocation.
  • the calculated optimal spacing ⁇ opt is the spacing that minimizes the spread between the N I wave numbers associated to the barycentric DOAs of the N I interfering cells. The advantage is that a brute-force minimization is avoided.
  • the embodiment is referred to a SIMO configuration for WiMAX-compliant systems, either fixed or mobile, but the same concepts and results are applicable to GSM, UMTS, etc., without changing the guidelines of the method.
  • each cell of a WiMAX-compliant system the multiple access is handled by a combination of time, frequency, and/or space division.
  • the transmission is organized in L time-frequency resource units, called blocks (or bursts), each containing K ⁇ N subcarriers and a time window of L s OFDM symbols.
  • blocks or bursts
  • Each block includes both coded data and pilot symbols. Pilot subcarriers are distributed over the block to allow the estimation of the channel/interference parameters.
  • a preamble containing only known training symbols could also be included in the block, as shown in the example of fig.1.
  • the preamble is used for the estimation of the channel/interference parameters, while the other pilot subcarriers are used to update the parameters' estimate along the block.
  • the same time-frequency unit may be allocated to more users in case SDMA is adopted. Every OFDM symbols of each block includes a subset of pilot subcarriers used to track the channel estimation in fast time-varying channels.
  • a subscriber station among those simultaneously active in the cell say SS 0 , transmitting (or receiving) signals to (or from) its own base station BS 0 (the communication can be either in the uplink or in the downlink).
  • the transmitter is assumed to employ a single antenna, while the receiver has N R antennas.
  • d i0 is the distance of the interferer SS i (with i ⁇ 0) from the base station BS 0 of the user of interest.
  • Data symbols can be generated according to an adaptive modulation-coding scheme where the transmission mode is selected based on the channel state (see, as an example, the transmission modes for IEEE-802.16-2004 in TABLE 1 (APPENDIX A) .
  • ⁇ ( ⁇ ) denotes the Dirac delta, while the index n spans the subcarriers.
  • the channel vector h k is assumed to be constant within the block.
  • the interferer SS 1 may stop at any given time and a new terminal may become active in the cell, generating an abrupt change in the signal interfering on user SS 0 .
  • the interference covariance could also vary within the block, on each OFDM symbol.
  • H H ⁇ ⁇ F T .
  • the multiplication by F in (3) performs the DFT transformation of the matrix H ⁇ by rows.
  • the propagation channel between SS 0 and BS 0 ( fig.3 ), the space-time matrix H ⁇ is assumed to be the superposition of N p paths' contributions.
  • Each path, say the r th is described by a direction of arrival (DOA) at the receiving array ( ⁇ 0, r ), a delay ( ⁇ 0, r ) and a complex fading amplitude ( ⁇ 0, r ):
  • DOA direction of arrival
  • Possible values of the parameters indicated by expression (7) are given by known multipath models, for example the temporal ones called SUI enriched with a characterization of the spatial interference (SUI-ST); see also Table 2 (APPENDIX A).
  • P 0 T is limited by the maximum power available at the SSs, i.e. P 0 T ⁇ P max T .
  • the power random fluctuations described above have to be ascribed to variations of the user position inside the cell.
  • the transmission mode selected (from those listed in Table 1 ) by the i th user (i ⁇ 0) and the corresponding transmitted power will be functions of the path loss over the distance d i and the shadowing over the link SS i - BS i .
  • fig.4 shows the transmission mode T(d) (in dotted spaced scale) and the corresponding power P (T) ( d ) required by a SS at distance d from its own BS.
  • the power transmitted by the i th interferer has to be increased with respect to (13) to compensate the shadowing fluctuations S i ⁇ N 0 ⁇ ⁇ s 2 among SS i and BS i .
  • P max T min P ⁇ T d i + S i ; P max T
  • a possible interference scenario is based on planning Q4 (Q is meaning square cells and 4 is the frequency reuse factor).
  • Q is meaning square cells and 4 is the frequency reuse factor.
  • the considered BS 0 receives the useful signal from SS 0 and three first-ring interfering signals from SS 1 , SS 2 , and SS 3 located in the centre of their cells and transmitting on the same frequency as SS 0 .
  • the useful and interfering signals are transmitted with the following characteristics:
  • the DOA of the interferer impinging on the array is thus discriminated without equivocation (alias), if for every angle ⁇ s a different wave number ⁇ s is obtained.
  • a good suppression of the interference is achieved by placing at least a zero of the directivity function in correspondence of the direction of each interferer.
  • three degrees of freedom (given by the number of antennas minus 1) are needed.
  • the remaining two can be used to superimpose two other zeros in the same direction of the first one, obtaining a larger attenuation.
  • AAP Antenna Array Pattern
  • ⁇ max ⁇ max
  • ⁇ opt n ⁇ 2.24 ⁇ .
  • the i th barycentric DOA is calculated by executing a weighted average extended to the N p ⁇ S directions of arrival of the N p paths by the S points of a grid indicative of the positions spanned by the i th interfering station inside its cell, weighting each DOA by the power received on that path.
  • ⁇ i B ⁇ the objective function
  • ⁇ opt 1.8 ⁇ is substantially confirmed by the unrestricted approach as a good trade-off between beamforming and diversity.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Radio Transmission System (AREA)
EP06425093A 2006-02-16 2006-02-16 Verfahren zur Optimierung des Abstandes zwischen Empfangsantennen eines Arrays als Gegenmassnahme gegen Interferenz und Fading in zellularen Systemen Withdrawn EP1826872A1 (de)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP06425093A EP1826872A1 (de) 2006-02-16 2006-02-16 Verfahren zur Optimierung des Abstandes zwischen Empfangsantennen eines Arrays als Gegenmassnahme gegen Interferenz und Fading in zellularen Systemen
PCT/EP2007/001238 WO2007093384A1 (en) 2006-02-16 2007-02-13 Method for optimizing the spacing between receiving antennas of an array usable for counteracting both interference and fading in cellular systems
CNA2007101379975A CN101083498A (zh) 2006-02-16 2007-02-16 优化阵列的接收天线间的间距的方法

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EP06425093A EP1826872A1 (de) 2006-02-16 2006-02-16 Verfahren zur Optimierung des Abstandes zwischen Empfangsantennen eines Arrays als Gegenmassnahme gegen Interferenz und Fading in zellularen Systemen

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CN (1) CN101083498A (de)
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101340648B (zh) * 2008-08-11 2012-01-11 中兴通讯股份有限公司 一种多用户波束赋形发射权值的生成方法
CN101425832B (zh) * 2008-11-10 2012-09-26 中兴通讯股份有限公司 一种基于零陷展宽的自适应多用户波束成形方法
RU2530292C1 (ru) * 2012-04-20 2014-10-10 Хуавэй Текнолоджиз Ко., Лтд. Антенна, базовая станция и способ обработки диаграммы направленности

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110098854B (zh) * 2016-11-29 2022-07-12 摩托罗拉移动有限责任公司 确定用于视距mimo通信的参数和条件的方法和装置
CN108966211B (zh) * 2017-09-30 2021-08-06 深圳大学 安全的无线通信物理层斜率认证方法和装置

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0755090A1 (de) * 1995-07-18 1997-01-22 Nortel Networks Corporation Anordnung zur Antennenstrahlsteuerung der Abwärtsrichtung
US6056780A (en) * 1996-09-20 2000-05-02 Thomson-Csf Method for the positioning of electromagnetic sensors or transmitters in an array
US20050001765A1 (en) * 2003-07-03 2005-01-06 Samsung Electronics Co., Ltd. Combined beamforming-diversity wireless fading channel demodulator using adaptive sub-array group antennas, signal receiving system and method for mobile communications

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0755090A1 (de) * 1995-07-18 1997-01-22 Nortel Networks Corporation Anordnung zur Antennenstrahlsteuerung der Abwärtsrichtung
US6056780A (en) * 1996-09-20 2000-05-02 Thomson-Csf Method for the positioning of electromagnetic sensors or transmitters in an array
US20050001765A1 (en) * 2003-07-03 2005-01-06 Samsung Electronics Co., Ltd. Combined beamforming-diversity wireless fading channel demodulator using adaptive sub-array group antennas, signal receiving system and method for mobile communications

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
"Optimal design of linear arrays in a TDMA cellular system with Gaussian interference", SIGNAL PROCESSING ADVANCES IN WIRELESS COMMUNICATIONS, 2005 IEEE 6TH WORKSHOP ON NEW YORK, NY, USA JUNE 2-8, 2005, PISCATAWAY, NJ, USA,IEEE, 2 June 2005 (2005-06-02), pages 485 - 489, XP010834466, ISBN: 0-7803-8867-4 *
S. SAVAZZI; O. SIMEONE; U. SPAGNOLINI: "Optimal design of linear arrays in a TDMA cellular system with Gaussian interference", IEEE PROC. SPAWC, 2005

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101340648B (zh) * 2008-08-11 2012-01-11 中兴通讯股份有限公司 一种多用户波束赋形发射权值的生成方法
CN101425832B (zh) * 2008-11-10 2012-09-26 中兴通讯股份有限公司 一种基于零陷展宽的自适应多用户波束成形方法
RU2530292C1 (ru) * 2012-04-20 2014-10-10 Хуавэй Текнолоджиз Ко., Лтд. Антенна, базовая станция и способ обработки диаграммы направленности

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CN101083498A (zh) 2007-12-05

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