Cai, Xuesong

Fan, Wei

Hanpinitsak, Panawit

Pedersen, Gert Frølund

Saito, Kentaro

Takada, Jun-ichi

Zhang, Guojin

English

This paper presents the characteristics of the mmwave propagation channel in hall scenario at the frequency bands of 9−11GHz and 27−29GHz. The spherical propagation parameters, i.e. delay, azimuth, elevation, source distance and complex amplitude are estimated by the high resolution parameter estimation (HRPE) algorithm. Based on the results, the channel characteristics, e.g. path loss, delay spread, and angle spread are analyzed for different mm-wave bands. The results reveal that the line of sight and specular components are dominant in such large size scenario at 9−11GHz and 27−29GHz bands, and little differences in the characteristics between the two bands can be observed

    Aalborg UniversitetMillimeter-Wave Channel Characterization in Large Hall Scenario at the 10 and 28 GHzBandsZhang, Guojin; Hanpinitsak, Panawit ; Cai, Xuesong; Fan, Wei; Saito, Kentaro; Takada, Jun-ichi ; Pedersen, Gert FrølundPublished in:13th European Conference on Antennas and Propagation (EuCAP)Publication date:2019Document VersionAccepted author manuscript, peer reviewed versionLink to publication from Aalborg UniversityCitation for published version (APA):Zhang, G., Hanpinitsak, P., Cai, X., Fan, W., Saito, K., Takada, J., & Pedersen, G. F. (2019). Millimeter-WaveChannel Characterization in Large Hall Scenario at the 10 and 28 GHz Bands. In 13th European Conference onAntennas and Propagation (EuCAP) [8739446] IEEE.General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright ownersand it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.            ? Users may download and print one copy of any publication from the public portal for the purpose of private study or research.            ? You may not further distribute the material or use it for any profit-making activity or commercial gain            ? You may freely distribute the URL identifying the publication in the public portal ?Take down policyIf you believe that this document breaches copyright please contact us at vbn@aub.aau.dk providing details, and we will remove access tothe work immediately and investigate your claim.Millimeter-Wave Channel Characterization in LargeHall Scenario at the 10 and 28 GHz BandsGuojin Zhang1, Panawit Hanpinitsak2, Xuesong Cai1, Wei Fan1, Kentaro Saito2, Jun-ichi Takada2,and Gert Frølund Pedersen1.1Department of Electronic Systems, Section Antennas, Propagation and Millimetre-wave Systems (APMS),Aalborg University, Aalborg, 9220, Denmark.2Department of Transdisciplinary Science and Engineering, School of Environment and Society,Tokyo Institute of Technology, Tokyo, Japan.Email: 1{guojin, xuc, wfa, gfp} @es.aau.dk, 2 {hanpinitsak.p@ap.ide.titech.ac.jp, saitouken@tse.ens.titech.ac.jp,takada@ide.titech.ac.jp.}Abstract—This paper presents the characteristics of the mm-wave propagation channel in hall scenario at the frequencybands of 9−11 GHz and 27−29 GHz. The spherical propaga-tion parameters, i.e. delay, azimuth, elevation, source distanceand complex amplitude are estimated by the high resolutionparameter estimation (HRPE) algorithm. Based on the results,the channel characteristics, e.g. path loss, delay spread, andangle spread are analyzed for different mm-wave bands. Theresults reveal that the line of sight and specular componentsare dominant in such large size scenario at 9−11 GHz and27−29 GHz bands, and little differences in the characteristicsbetween the two bands can be observed.Index Terms—Millimeter-wave, path loss, delay spread andangle spread.I. INTRODUCTIONThe next generation communication system (5G) is movingtowards frequency bands above 6 GHz, due to the plentyof available spectrum and higher data traffic supported atmillimeter wave (mm-wave) bands. Accurate knowledge of thechannel propagation characteristics in mm-wave frequenciesband is important for mm-wave system design and perfor-mance evaluation [1].Extensive measurement campaigns have been conductedfor mm-wave channels, with focusing on the comparison ofchannels in different frequency bands in the same environment[2]–[4]. In [2], the measurements were conducted in a typicalindoor office environment at 28 GHz and 73 GHz frequencybands. Large-scale path loss and temporal statistic are pro-vided, using rotatable directional horn antennas. In [5], thefrequency dependency of propagation parameters, e.g. powerdelay profile, delay spread, path loss and shadow fading wereinvestigated in three different indoor environments, such ashall, meeting room and corridor scenarios. In [6], the largescale parameters, i.e. path-loss, shadowing, cross-polarizationpower ratio, delay spread and coherence bandwidth wereinvestigated in various indoor environments at 11 GHz, in-cluding two hall scenarios and three rooms. To the author’sbest knowledge, the analysis of the channel characteristicsat different frequency bands in these indoor cases, is stilllimited comparing the power spectrum and delay spread inmost papers.In this paper, the comparison of propagation characteris-tics with total 20 Tx antenna locations at 9−11 GHz and27−29 GHz bands in large hall scenario are investigated. Thehigh resolution parameter estimation (HRPE) algorithm is usedfor extracting the information of delay, angle and amplitude,which are used for calculating the characteristics, such as pathloss, delay spread and angle spread.The rest of this paper is organized as follows. In Section II,the measurement campaign is presented. Section III describesthe channel characteristics, and the results of propagation pa-rameters are analyzed. Section IV summarizes the conclusions.II. MEASUREMENT CAMPAIGNFig. 1 illustrates the top-view sketch of the hall scenarioin Aalborg University, where the measurement campaignwas conducted at the frequency band of 9−11 GHz and27−29 GHz, using a channel sounder [3], [7] based on a vectornetwork analyzer (VNA). The measurement setup parametersare depicted in Table I. The shape of the hall is irregular, with39 m from west to east, 20 m from north to south and 10m height from the ground to the ceiling. The four big yellowventilation tubes and six small white pillars are located aroundthe hall.The commercial biconical antenna SZ-2003000/P [8] wasused as transmitter (Tx) antenna and homemade biconicalantenna [9] was used as receiver (Rx) antenna, as shown inFig. 2. The Rx antenna was rotated clockwise on a rotatingpedestal with a pre-set radius of 0.24 m with 1 degree rotatingsteps, to form a large-scale uniform circular array (UCA) with360 elements. The antenna gains of commercial antenna are2.75 dBi at 10 GHz and 4.8 dBi at 28 GHz. For the homemadeantenna, the gains are 3.5 dBi at 10 GHz and 6 dBi at 28 GHz.A total of 20 spatial snapshots were measured by moving theTx antenna and the Rx antenna was located near the yellowventilation tubes as shown in Fig. 1. Each Tx in each row wasspaced 1 m apart. The height of the Tx and Rx antennas isTABLE IMEASUREMENT SETUP.Room HallDimension (m3) 39× 20× 10Tx antenna Commercial biconical SZ-2003000/PRx antenna Homemade biconical antennaCenter frequency 10, 28 GHzBandwidth 2 GHzTx\Rx antenna height 1.50 mFrequency sweep points 360Frequency samples 750UCA radius 0.24 mmounted at 1.50 m. The measurement was conducted with abandwidth of 2 GHz and 750 samples were collected for eachfrequency band.Fig. 1. Top view of the hall scenario with 20 Tx locations and single Rxlocation.III. RADIO CHANNEL CHARACTERIZATIONThe measured raw data is processed by the hanning windowand inverse Fourier transform (IFT), then the average powerdelay profiles (APDPs), which can be obtained by the channelimpulse response (CIR) hm,n(τ) asPm(τ) =1NN∑n=1|hm,n(τ)|2 (1)where hm,n(τ) represents the CIR at m-th delay sample andn-th measured element.In order to study the channel characteristics of the mm-wavespherical propagation, the HRPE algorithm [10] is applied toFig. 2. The photograph of Rx (left) and Tx (right) antennas.derive the parameters of the UCA channels, i.e. azimuth an-gles, elevation angles, delays, source distances and amplitudesof multipath components (MPCs). The spatial-temporal CIRh(t; τ, θ, φ, d) can be described ash(t; τ, θ, φ, d) =L∑l=1αlδ(τ − τl)δ(θ − θl)δ(φ− φl)δ(d− dl),(2)where L is the number of spherical waves impinge into theUCA, αl represents the complex amplitude, τl is the propa-gation delay, θl and φl represent the azimuth and elevationangles of the l-th path, respectively. dl is the propagationdistance between the UCA center and the last source pointduring the propagation route of the l-th path, respectively.These parameters are used for calculating the characteristicsof the channel propagation in this section.A. Path lossPath Loss is a fundamental channel model for estimatingthe link budget and coverage in cellular network [11]. Thepath loss of each Tx location can be calculated by the sumpower of the CIRs, which can be represented asPL = PTx − PRx +GTx +GRx[dB] (3)where PTx and PRx are the transmit and received power,respectively. GTx and GRx are the the gains of the Tx and Rxantennas used at the measurement frequency, respectively. Thepath loss can be represented by the integrating all the powerof the paths, can be obtained by the CIRs asPTx − PRx =M∑m=1Pm(τ) (4)Table II show the path loss model fitting results, in which thepath loss model is expressed byPL(d)[dB] = a+ 10 · blog10(d[m]) +Xσ (5)where a is the fading constant and b is the path loss exponent,which are both the least-square fits of floating intercept and theTABLE IIPATH LOSS MODEL PARAMETERS.Frequency band (GHz) a b Xσ10 51.651 1.712 0.19528 63.725 1.525 0.468slope. d represents the distance between Tx and Rx antennas,with the reference distance set as 1 m. Xσ denotes theshadowing variation, which is represented by the log-normalrandom variable with standard deviation σ.Fig. 3(a) shows the measured path loss compared with thefree space path loss at the frequency bands of 9-11 GHz and27-29 GHz. The measured path loss at 9-11 GHz is little lowerthan free space path loss. While, in case of 27-29 GHz band,the measured path loss was roughly the same as free spacepath loss. It can also be seen from the results in Table II thatthe path loss exponents b are similar to 2 due to large size ofthe hall scenario. These results match the results in [2] whichreported that the b decreases with frequencies and values arehigher than 1.5.B. Delay SpreadThe delay spread is widely used for characterizing the MPCsrichness of the channels [12]. In this section, delay spread iscalculated by two methods. The first method is based on themeasured raw data with dynamic range of 25 dB, and thesecond is based on the delay information estimated by HPREalgorithm.The delay spread is calculated as the second-order centralmoments of APDPs. The mean delay τ̄ and root mean squaredelay spread στ with the first method can be computed as [12]τ̄ =∑Mm=1 Pm(τ) · τ∑Mm=1 Pm(τ), (6)στ =√√√√∑Mm=1 Pm(τ) · τ2∑Mm=1 Pm(τ)− τ̄2. (7)For the second method, Pm(τ) need to be replaced by thesquare of complex amplitude |αl|2 obtained by the HPREalgorithm. Besides that, the delay sample m and M shouldbe exchanged with the number of the estimated paths l and L,respectively.The similar trend by the two methods at 10 GHz and 28GHz can be observed from Fig. 3(b). The difference betweenthe two methods at the same frequency is due to the affectof the sidelobes in measured raw data. Thus, more accurateresults can be achieved by the HPRE algorithm. The lowestvalues of delay spread can be seen at position 7-10 and 17-18,where is the smallest Tx-Rx distance.C. Angle SpreadBecause the estimated elevation angles are almost close to90 degrees, only azimuth angles are investigated. The anglespread σθ can be calculated, as defined in [10], [13],(a)(b)(c)Fig. 3. The channel characteristics in hall scenario at total 20 Tx locations.(a) Path Loss. (b) Delay Spread. (c) Angle Spread.σθ =√√√√−2log(∣∣∣∣∣∑Ll=1 exp(jθl) · |αl|2∑Ll=1 |αl|2∣∣∣∣∣). (8)The large deviation in the values of angle spread is depictedin Fig. 3(c) at positions 5-10 and 12-16, 20. That is becausepositions 5-10 are much close to the Rx antenna, yellow venti-lation tubes and pillars, the strong reflections at these positionsare mainly from the white pillars and yellow ventilation tubesnearby with small range of azimuth. While positions 12-16 and20 are relatively far from the Rx antenna, yellow ventilationtubes and pillars, the reflections are mainly from the wallsaround with large range of azimuth.According to the power angle delay profiles (PADPs) ofposition 8 obtained by the HRPE algorithm in Fig. 4(a), themain specular components after the LOS path are identifiedand plotted in Fig. 4(b). It could be seen that strong specularreflected paths are mainly contributed by the yellow ventilationtubes and white pillars. On the other hand, the main specular(a)(b)Fig. 4. The PADPs and identified paths of Tx positions 8 at 27 GHz-29 GHzin Hall.components after the LOS path are sparse at 10 and 28 GHzbands and the LOS components are dominant at the positionswith small Tx-Rx distance.IV. CONCLUSIONIn this paper, the radio channel of hall scenario is character-ized at frequency bands of 9−11 GHz and 27−29 GHz. Basedon the virtual uniform circular array (UCA) system and highresolution parameter estimation (HRPE) algorithm, specularpropagation paths are identified and their delay, azimuth andelevation information are estimated. The properties of the radiochannel at 9−11 GHz and 27−29 GHz bands are studied interms of path loss, angle spread, and delay spread. The resultshows that the differences between two frequency bands aremostly minor. The measured path loss at 27−29 GHz is similarwith the free space path loss, duo to dominant LOS path. Thepath loss exponents b are higher than 1.5 at 9−11 GHz and27−29 GHz, due to the large size of the hall scenario. It canalso be observed that the values of delay spread obtained byHRPE algorithm are more accurate than that by measured rawdata, with the range of 6−20 ns. The values of angle spreadare mainly ranged between 12.75 ◦ and 41 ◦. In order to revealfurther channel characteristics in non-line of sight scenarios,more measurements and simulation data are still needed.REFERENCES[1] T. S. Rappaport, S. Sun, R. Mayzus, H. Zhao, Y. Azar, K. Wang, G. N.Wong, J. K. Schulz, M. Samimi, and F. Gutierrez, “Millimeter wavemobile communications for 5G cellular: It will work!” IEEE Access,vol. 1, pp. 335–349, 2013.[2] G. R. Maccartney, T. S. Rappaport, S. Sun, and S. Deng, “Indooroffice wideband millimeter-wave propagation measurements and channelmodels at 28 and 73 GHz for ultra-dense 5G wireless networks,” IEEEAccess, vol. 3, pp. 2388–2424, 2015.[3] W. Fan, I. Carton, J. Ø. Nielsen, K. Olesen, and G. F. Pedersen,“Measured wideband characteristics of indoor channels at centimetricand millimetric bands,” EURASIP Journal on Wireless Communicationsand Networking, vol. 2016, no. 1, p. 58, Feb 2016. [Online]. Available:https://doi.org/10.1186/s13638-016-0548-x[4] J. Vehmas, J. Jarvelainen, S. L. H. Nguyen, R. Naderpour, andK. Haneda, “Millimeter-wave channel characterization at helsinki airportin the 15, 28, and 60 GHz bands,” in 2016 IEEE 84th VehicularTechnology Conference (VTC-Fall), Sept 2016, pp. 1–5.[5] S. Geng and P. Vainikainen, “Frequency and bandwidth dependency ofUWB propagation channels,” in 2006 IEEE 17th International Sym-posium on Personal, Indoor and Mobile Radio Communications, Sept2006, pp. 1–5.[6] M. Kim, Y. Konishi, Y. Chang, and J. Takada, “Large scale parame-ters and double-directional characterization of indoor wideband radiomultipath channels at 11 GHz,” IEEE Transactions on Antennas andPropagation, vol. 62, no. 1, pp. 430–441, Jan 2014.[7] P. Hanpinitsak, K. Saito, W. Fan, J.-i. Takada, and G. F. Pedersen,“Frequency characteristics of path loss and delay-angular profile ofpropagation channels in an indoor room environment in SHF bands,”in Mobile Communication Workshop, 2017.[8] ainfoinc, “SZ-2003000-P.pdf [online].” Available: http://www.ainfoinc.com/en/pro pdf/new products/antenna/Bi-Conical%20Antenna/tr SZ-2003000-P.pdf, Tech. Rep., (2018, June 5).[9] S. S. Zhekov, A. Tatomirescu, and G. F. Pedersen, “Antenna for ultra-wideband channel sounding,” IEEE Antennas and Wireless PropagationLetters, vol. 16, pp. 692–695, 2017.[10] X. Cai and W. Fan, “A complexity-effcient high resolution propagationparameter estimation algorithm for ultra-wideband large-scale uniformcircular array,” submitted to IEEE Trans. Commun., 2018.[11] J. Ko, Y. Cho, S. Hur, T. Kim, J. Park, A. F. Molisch, K. Haneda,M. Peter, D. Park, and D. Cho, “Millimeter-wave channel measurementsand analysis for statistical spatial channel model in in-building and urbanenvironments at 28 GHz,” IEEE Transactions on Wireless Communica-tions, vol. 16, no. 9, pp. 5853–5868, Sept 2017.[12] X. Cai, X. Yin, X. Cheng, and A. P. Yuste, “An empirical random-clustermodel for subway channels based on passive measurements in UMTS,”IEEE Trans. Commun., vol. 64, no. 8, pp. 3563–3575, Aug 2016.[13] 3GPP, “Study on channel model for frequencies from 0.5 to 100 GHz,”(3GPP TR 38.901 version 14.0.0 Release 14), 2018.

Millimeter-Wave Channel Characterization in Large Hall Scenario at the 10 and 28 GHz Bands

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Millimeter-Wave Channel Characterization in Large Hall Scenario at the 10 and 28 GHz Bands

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