A method for localization in mmwave MIMO networks in NLOS channel condition

Abstract

A method suitable for determining location of a multiple input-multiple output (MIMO) receiver in a system comprising a MIMO transmitter (100) having a predetermined location where said MIMO transmitter (100) and said MIMO receiver (200) has non-line-of-sight (NLOS) condition therebetween and at least a scatterer (300) for reflecting signals between said MIMO receiver (200) and said MIMO transmitter (100).

Description

[0001] A METHOD FOR LOCALIZATION IN MMWAVE MIMO NETWORKS IN NLOS CHANNEL CONDITION

[0002] TECHNICAL FIELD

[0003] Invention relates to a method suitable for determining location of a multiple input-multiple output (MIMO) receiver in a system comprising a MIMO transmitter having a predetermined location where said MIMO transmitter and said MIMO receiver has non-line-of-sight (NLOS) channel condition therebetween and at least a scatterer for reflecting signals between said MIMO receiver and said MIMO transmitter.

[0004] PRIOR ART

[0005] While Global Navigation Satellite Systems (GNSS), like the widely used Global Positioning System (GPS), serve as the default solution for outdoor positioning with a clear sky view, there is currently no dominant technology suitable for GNSS-deprived environments. These include densely built city centers, urban canyons, and particularly the interiors of buildings where satellite signals face significant attenuation or complete blockage, often compounded by multipath propagation effects. Considering that people spend a substantial portion of their time indoors, coupled with the fact that the majority of cellular calls and data connections originate from indoor locations, there is a growing demand for highly precise indoor localization systems [1]-

[0006] The existing localization services provided by global navigation satellite systems, wireless local area networks (WLAN), or current cellular networks typically achieve, at best, meter-level localization accuracy in environments with high interference [2], Achieving centimeter-level accuracy, a requirement for many emerging applications of 5G and beyond, such as intelligent interactive networks, smart cities, and automated factories, poses a challenge with these coarse localization services. To address the demands of these emerging applications, the foundational technologies of 5G and beyond, such as millimeter wave (mmWave), massive multiple-input multiple-output (MIMO), and ultra-dense networks (UDNs), can be harnessed to enhance localization performance. MmWave communication, operating at frequencies around 30 GHz and higher, with signal bandwidth reaching up to 2 GHz, offers high temporal resolution for time-based localization. Additionally, extremely large-scale MIMO (XL-MIMO) systems, equipped with thousands of antenna elements, can achieve angular resolution of less than 1 degree for angle-based localization. Furthermore, UDNs are anticipated to increase the likelihood of line-of-sight (LoS) links, presenting an opportunity for enhancing localization performance.

[0007] The localization performance within mmWave mMIMO networks is commonly constrained by non-line-of-sight (NLoS) propagation. Existing literature proposes three methods to address this NLoS channel condition. The first method relies on leveraging statistical information about NLoS errors. By assuming a scattering model of the environment, one can derive the statistics of signal measurements. Subsequently, well-established techniques such as maximum a posteriori (MAP) or maximum likelihood (ML) can be applied to mitigate the impact of NLoS errors. However, the challenge lies in obtaining an accurate model, which may vary with terrain and building construction. The second method utilizes both NLoS and line-of-sight (LoS) measurements, assigning appropriate weights to minimize the influence of NLoS contributions. While effective even in scenarios without LoS measurements, this method's solution is deemed unreliable due to the persistent presence of NLoS errors [3]. The third method involves identifying and discarding NLoS measurements, conducting localization solely based on LoS measurements. Essentially, this method transforms the NLoS identification problem into a statistical detection challenge, treating NLoS and LoS conditions as two hypotheses. The objective is to devise a metric distinguishing between NLoS and LoS hypotheses. For example, the identification of NLoS paths can be based on the statistics of range measurements. Typically, NLoS range measurements, exhibiting a positively biased non-Gaussian distribution, tend to possess a larger variance compared to their LoS counterparts with a Gaussian distribution. However, in challenging environments, nearly all measurements may originate from NLoS paths, resulting in an insufficient number of LoS measurements for accurate localization.

[0008] Generally, NLoS localization techniques can be categorized into two groups. The first involves NLoS localization through signal measurements combined with a priori knowledge of the environment map. The second category focuses on localization using measurements obtained from scatters [4,5]. It's important to note that in the latter approach, NLoS measurements are initially identified, and subsequently, the geometric relationships among the transmitter, receiver, and scatters are utilized for localization. The authors in [5] examine a system model that accounts for a static environment, the presence of multipath clusters, a moving receiver, knowledge of transmitter position and initial receiver position, as well as the moving direction. In the literature, the localization in mmWave spectrum mostly requires LoS channel condition. Moreover, if there is NLoS channel condition along with LoS channel condition, both channel paths can be used to improve the localization performance. However, the localization in NLoS channel is the most challenging scenario. For these scenarios, environment map is used or channel impulse response is used to understand the scatters effects for the localization. Therefore, both methods use radio environment mapping. The first uses already an available map, and the latter generates a map from the channel impulse responses. Although there are a few solutions for only NLoS channel condition, the localization performance is not obtained satisfactorily, or the localization is not feasible if there is no radio environment mapping.

[0009] Considering a system model that there is one transmitter, scatterer in the environment, and receiver. The transmitter position is perfectly known and wants to estimate the receiver position. The transmitter can be a fixed base station and the receiver can be mobile user in 5G network for the considered system model. If the transmitter has only NLoS channel condition with the receiver, it cannot find an accurate receiver position by using time of arrival (TOA) and angle of arrival (AOA) parameters due to scattering. A practical scenario is mmWave communication with blockage for the considered system model. Therefore, the existing solution does not solve this localization problem. Therefore, current art requires improvements in order to solve above mentioned localization problem.

[0010] References:

[0011]

[0001] C. Laoudias, A. Moreira, S. Kim, S. Lee, L. Wirola and C. Fischione, "A Survey of Enabling Technologies for Network Localization, Tracking, and Navigation,” IEEE Communications Surveys & Tutorials, vol. 20, no. 4, pp. 3607-3644, Fourthquarter 2018.

[0012] [2] Z. Xiao and Y. Zeng, "An overview on integrated localization and communication towards 6G," Science China Information Sciences, vol. 65, pp. 1 -46, 2022.

[0013] [3] M. Ruble and I. Guveng, "Wireless localization for mmWave networks in urban environments," EURASIP journal on advances in signal processing, vol. 1 pp. 1 -19, 2018.

[0014] [4] K. Witrisal and et aL, "High-accuracy localization for assisted living: 5G systems will turn multipath channels from foe to friend," IEEE Signal Processing Magazine, vol. 33, no. 2, pp. 59-70, 2016. [5] C. Gentner, T. Jost, W. Wang, S. Zhang, A. Dammann and U. -C. Fiebig, "Multipath Assisted Positioning with Simultaneous Localization and Mapping," in IEEE Transactions on Wireless Communications, vol. 15, no. 9, pp. 6104-61 17, Sept. 2016.

[0015] All the problems mentioned above have made it necessary to make an innovation in the relevant technical field as a result.

[0016] BRIEF DESCRIPTION OF THE INVENTION

[0017] The present invention relates to a method to eliminate the above-mentioned disadvantages and bring new advantages to the relevant technical field.

[0018] An object of the invention is determining location of a MIMO receiver which is in communication with a MIMO transmitter in NLOS channel condition, through a scatterer.

[0019] Another object of the invention is determining location of a MIMO receiver, which is in communication with a MIMO transmitter in NLOS channel condition, through multiple scatterers.

[0020] Another object of the invention is to provide a method that determines location of a MIMO receiver, which is in communication with a MIMO transmitter in NLOS channel condition, through multiple scatterers with increased precision.

[0021] To achieve all the objects mentioned above and that will emerge from the following detailed description, the present invention relates to a method suitable for determining location of a multiple input-multiple output (MIMO) receiver in a system comprising a MIMO transmitter having a predetermined location where said MIMO transmitter and said MIMO receiver has non-line-of-sight (NLOS) channel condition therebetween and at least a scatterer for reflecting signals between said MIMO receiver and said MIMO transmitter. Accordingly, comprising steps of:

[0022] - realizing beam training by the MIMO transmitter and by the MIMO receiver, and determining a beam pair for communication;

[0023] - by MIMO transmitter, transmitting angle of departure (AOD) of a signal transmitted using determined beam pair to MIMO receiver and transmitting said predetermined location information of MIMO transmitter to MIMO receiver; - by MIMO receiver, determining angle of arrival (AOA) of a signal received using determined beam pair from MIMO transmitter;

[0024] - realizing monostatic sensing by MIMO receiver and / or by MIMO transmitter on the scatterer that reflects signals transmitted through the determined beam pair and determining a distance x’ between MIMO transmitter and the scatterer; and a distance y’ between MIMO receiver and the scatterer;

[0025] - by MIMO receiver acquiring the distance x’, and the distance y’; determining the location of the MIMO receiver using the distance x’, the distance y’, the location of MIMO transmitter, the AOA and the AOD. Thus, location of MIMO receiver may be determined in more precise manner without the need of a prior location knowledge of scatterers.

[0026] A possible embodiment of the invention is characterized in that comprising the steps of:

[0027] - realizing monostatic sensing by MIMO receiver on the scatterer that reflects signals transmitted through the determined beam pair and determining the distance y’ between MIMO receiver and the scatterer;

[0028] - by MIMO receiver determining time of arrival (TOA) of the signal received from MIMO transmitter through determined beam pair;

[0029] - by MIMO receiver, calculating a propagation distance d using said TOA;

[0030] - by MIMO receiver, estimating a distance x’ between the scatterer and the MIMO transmitter using formula d = x’ + y’.

[0031] Another possible embodiment of the invention is characterized in that comprising the steps of:

[0032] - realizing monostatic sensing by MIMO transmitter on the scatterer that reflects signals transmitted through the determined beam pair and determining the distance x’ between MIMO transmitter and the scatterer;

[0033] - transmitting the distance x’ to MIMO receiver;

[0034] - by MIMO receiver determining time of arrival (TOA) of the signal received from MIMO transmitter through determined beam pair;

[0035] - by MIMO receiver, calculating a propagation distance d using said TOA,

[0036] - by MIMO receiver, estimating a distance y’ between the scatterer and the MIMO receiver using formula d = x’ + y’.

[0037] Another possible embodiment of the invention is characterized in that comprising the steps of:

[0038] - realizing monostatic sensing by MIMO receiver on the scatterer that reflects signals transmitted through the determined beam pair and determining the distance y’ between MIMO receiver and the scatterer; - realizing monostatic sensing by MIMO transmitter on the scatterer that reflects signals transmitted through the determined beam pair and determining the distance x’ between MIMO transmitter and the scatterer.

[0039] Another possible embodiment of the invention is characterized by comprising the steps of:

[0040] - realizing monostatic sensing by MIMO transmitter on at least a first scatterer and at least a second scatterer that reflects signals transmitted through the determined beam pair and determining at least a distance eX1 and at least a distance eX2 between MIMO transmitter and the first scatterer and the second scatterer respectively,

[0041] - transmitting the distance eX1 and the distance eX2 to MIMO receiver;

[0042] - realizing monostatic sensing by MIMO receiver on one of the first scatterer or the second scatterer determining the distance eY between MIMO receiver and the first scatterer or the second scatterer;

[0043] - by MIMO receiver determining time of arrival (TOA) of the signal received from MIMO transmitter through determined beam pair and determining a distance d;

[0044] - determining which scatterer’s distance eY is determined by the MIMO receiver using below formula ith scatterer = min (distance d- (distance xi-distance eY)

[0045] - by MIMO receiver, using the distance of determined scatterer to MIMO transmitter (100) as the distance eX for location determination.

[0046] Another possible embodiment of the invention is characterized by comprising the steps of:

[0047] - realizing monostatic sensing by MIMO transmitter on at least a first scatterer and at least a second scatterer that reflects signals transmitted through the determined beam pair and determining at least a distance eX1 and at least a distance eX2 between MIMO transmitter and the first scatterer and the second scatterer respectively,

[0048] - transmitting the distance eX1 and the distance eX2 to MIMO receiver;

[0049] - if it is determined that there is more than one scatterer on determined beam pair, realizing monostatic sensing by MIMO receiver on at least the first scatterer and on at least the second scatterer determining the distance eY1 and the distance eY2 between MIMO receiver and the first scatterer and the second scatterer respectively;

[0050] - by MIMO receiver, determining location of the MIMO receiver by using distance eX1 and the distance eX2 considering the communication directional. Also the present invention relates to a system comprising a MIMO transmitter having a predetermined location where said MIMO transmitter and said MIMO receiver has non-line-of- sight (NLOS) channel condition therebetween and at least a scatterer for reflecting signals between said MIMO receiver and said MIMO transmitter wherein said system is configured to realize a method of claim 1 to 6 for determining location of a MIMO receiver.

[0051] BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 is a drawing illustrating schematic view of the system.

[0053] Figure 2 is a drawing illustrating how location is calculated.

[0054] Figure 3 is a drawing illustrating schematic view of the system with multiple scatterers.

[0055] Figure 4 is a drawing illustrating schematic view of the system with multiple scatterers.

[0056] Figure 5 is a drawing illustrating schematic view of the system with multiple scatterers.

[0057] Figure 5.1 is a drawing illustrating estimating location of the receiver with the system having multiple scatterers.

[0058] Figure 6 is a drawing illustrating beam training procedure.

[0059] REFERENCE NUMBERS GIVEN IN THE FIGURE

[0060] 100 MIMO transmitter

[0061] 200 MIMO receiver

[0062] 300 Scatterer

[0063] 301 First scatterer

[0064] 302 Second scatterer

[0065] 400 Blockage

[0066] 500 Beam Pair

[0067] 501 First beam

[0068] 502 Second beam

[0069] 510 Beam d distance d x Distance X y Distance Y y1 Distance Y1 y2 Distance Y2 x1 Distance X1 x2 Distance X2 a1 AOD a2 AOA

[0070] DETAILED DESCRIPTION OF THE INVENTION

[0071] In this detailed description, the subject matter is explained with references to examples without forming any restrictive effect only in order to make the subject more understandable.

[0072] Present invention is a method suitable for determining location of a multiple input-multiple output (MIMO) receiver in a system comprising a MIMO transmitter (100) having a predetermined location where said MIMO transmitter (100) and said MIMO receiver (200) has non-line-of-sight (NLOS) channel condition therebetween and at least a scatterer (300) for reflecting signals between said MIMO receiver (200) and said MIMO transmitter (100). The method realizes beam training for determining best beams for communication between MIMO receiver (200) and MIMO transmitter (100). The method then, determines location of scatterers (300) using MIMO transmitter location then determines location of receiver using scatterer (300) locations and data related to signal transmitted from MIMO transmitter (100) to MIMO receiver (200) such as angle of arrival, angle of departure, time of arrival.

[0073] Referring to figure 1 , the system comprises a MIMO transmitter (100) and a MIMO receiver (200). MIMO transmitter (100) and MIMO receiver (200) are in state of non-line of sight (NLOS) with each other. In other words, signals transmitted to MIMO receiver (200) is blocked by a blockage (400). A scatterer (300) is provided between MIMO transmitter (100) and MIMO receiver (200) for reflecting / scattering signals between them. Signal transmitted from MIMO transmitter (100) is reflected / scattered by scatterer (300) to MIMO receiver (200). System uses mmWave communication.

[0074] MIMO transmitter (100), may be provided on a communication device which has a known / predetermined location. Said device comprises receiving elements in order to communicate with MIMO receiver (200) in both directions (receive-transmit). Said communication device for instance may be a base station. MIMO receiver (200) may be provided on another communication device, which has an unknown location. The device comprises transmitting elements in order to communicate with MIMO receiver (200) in both directions. The communication device may be for instance a user equipment.

[0075] In order to determine the location of MIMO receiver (200), following steps are realized. MIMO transmitter (100) and MIMO receiver (200) realizes beam training and determines a beam pair (500) for communication.

[0076] MIMO transmitter (100) transmits angle of departure (AOD) of a signal transmitted using determined beam pair to MIMO receiver (200). MIMO transmitter (100) transmits its predetermined location information to MIMO receiver (200). MIMO receiver (200), determines angle of arrival (AOA) of signal received using determined beam pair from MIMO transmitter (100). MIMO receiver (200) and / or MIMO transmitter (100) realize monostatic sensing on the scatterer (300) that reflects signals transmitted through the determined beam pair. A distance eX and a distance eY is determined after realizing monostatic sensing. The distance eX is a distance between MIMO transmitter (100) and the scatterer (300); and the distance eY is a distance between MIMO receiver (200) and the scatterer (300). Then MIMO receiver (200) acquires the distance eX, and the distance eY; determines the its (MIMO receiver (200)) location using the distance eX, the distance eY, the location of MIMO transmitter (100), the AOA and the AOD. Distance eX and distance eY are the estimated versions of actual distance between MIMO transmitter (100) and scatterer (300) (distance X (x) and MIMO receiver (200) and scatterer (300) (distance Y (y)).

[0077] Referring to figure 2, location of transmitting point is known. The distance between transmitting point and scatterer (300) is estimated and AOD is estimated. The location of scatterer (300) can be calculated based on those known and estimated parameters. The distance between scatterer (300) and receiver is estimated. Since location of scatterer (300) and angle of arrival is also obtained, MIMO receiver’s (200) location can be calculated using those information.

[0078] In a possible embodiment, monostatic sensing is realized by MIMO receiver (200) on the scatterer (300) that reflects signals transmitted through the determined beam pair and MIMO receiver (200) determines the distance eY between MIMO receiver (200) and the scatterer (300). MIMO receiver (200) determines the time of arrival (TOA) of the signal received from MIMO transmitter (100) through determined beam pair. MIMO receiver (200), calculates a propagation distance d (d) using said TOA. Propagation distance is summation of the distance between MIMO transmitter-scatterer and the distance between MIMO receiver-scatterer. MIMO receiver (200), estimates a distance eX between the scatterer (300) and the MIMO transmitter (100) using formula d = eX + eY. Thus, acquiring distance eX and distance eY. Then MIMO receiver (200) acquires the distance eX, and the distance eY; determines the its (MIMO receiver (200)) location using the distance eX, the distance eY, the location of MIMO transmitter (100), the AOA and the AOD.

[0079] In a possible embodiment, monostatic sensing is realized by MIMO transmitter (100) on the scatterer (300) that reflects signals transmitted through the determined beam pair and MIMO transmitter (100) determines the distance eX between MIMO transmitter (100) and the scatterer (300). MIMO transmitter (100) transmits the distance eX to MIMO receiver (200). MIMO receiver (200) determines the time of arrival (TOA) of the signal received from MIMO transmitter (100) through determined beam pair. MIMO receiver (200), calculates a propagation distance d (d) using said TOA. MIMO receiver (200), estimates a distance eY between the scatterer (300) and the MIMO transmitter (100) using formula d = eX + eY. Thus, acquiring distance eX and distance eY . Then MIMO receiver (200) acquires the distance eX, and the distance eY; determines the its (MIMO receiver (200)) location using the distance eX, the distance eY, the location of MIMO transmitter (100), the AOA and the AOD.

[0080] In a possible embodiment, monostatic sensing is realized by both MIMO receiver (200) and the MIMO transmitter (100) on the scatterer (300) that reflects signals transmitted through the determined beam pair. The distance eY between MIMO receiver (200) and the scatterer (300) is determined and the distance eX between MIMO transmitter (100) and the scatterer (300) is determined. Then MIMO receiver (200) acquires the distance eX, and the distance eY; determines the its (MIMO receiver (200)) location using the distance eX, the distance eY, the location of MIMO transmitter (100), the AOA and the AOD.

[0081] Receiver position and the scatterer position may be estimated using below formula, where transmitter position is (pt.r ptin 2-dimensional plane, AOD and AOA are denoted by adand aa, and the scatterer distances are denoted byXiandyi. Then, the scatterer position on the angle adcan be estimated as

[0082] Then, the receiver position on the angle aacan be estimated as Note that, only 2 dimensional calculation is given here as example. 3 dimensional calculations would use similar formulas suitable for 3 dimensional location calculation.

[0083] The detecting the scatterers (300) in the environment is known in the art. Present invention performs monostatic sensing on the beam that has the best signal quality (determined beam pair).

[0084] Referring to figure 3 and 4, in a possible embodiment multiplicity of scatterers (300) may be present. A first scatterer (301 ) and the second scatterer (302) may have distance X1 , distance X2 to MIMO transmitter (100) respectively. MIMO transmitter (100) determines distance eX1 and distance eX2 using monostatic sensing. MIMO transmitter (100), transmits the distance eX1 and the distance eX2 to MIMO receiver. One of the first scatterer (301 ) and the second scatterer (302) have a distance Y to MIMO receiver (200). MIMO receiver (200) determines a distance eY using monostatic sensing and receives distance eX1 and distance eX2 from MIMO transmitter (100). The MIMO receiver (200) calculates a distance d using time of arrival of the signal received through the scatterer that the distance y is determined. Then MIMO receiver (200) determines the scatterer (300) that the MIMO receiver determined the distance eY of using following formula: ith scatterer = min (d - (eX1 + eY)), d-(eX2+eY))

[0085] In above embodiment, MIMO receiver (200) only detects one scatterer after monostatic sensing. The other scatter’s signal may be blocked by an object (figure 4) or may be unresolvable at the MIMO receiver (200) side (figure 3). In other words, MIMO receiver (200) cannot distinguish which signal is reflected from which scatterer (300).

[0086] MIMO receiver (200) then uses the distance eX1 or distance eX2 depending on the determined scatterer and calculates its location using selected scatterer’s (300) related distances such as calculated in the previous embodiments.

[0087] Referring to figure 5, in a possible embodiment multiplicity of scatterers (300) may be present. A first scatterer (301 ) and the second scatterer (302) may have distance X1 , distance X2 to MIMO transmitter (100) respectively. MIMO transmitter (100) determines distance eX1 and distance eX2 using monostatic sensing. The first scatterer (301 ) and the second scatterer (302) have a distance Y1 and a distance Y2 to MIMO receiver (200) respectively. MIMO receiver (200) determines a distance eY1 and eY2 using monostatic sensing and receives distance eX1 and distance eX2 from MIMO transmitter (100). If MIMO receiver (200) determines more than one scatterers (300) and determines more than one distance eY; it calculates its location based on distance eY1 and the distance eY2. This significantly improves calculation time and resources used.

[0088] Figure 5.1 depicts calculation method of the location. Since the communication is directional, when distance to two scatterer is determined, location in 2 dimentions can be determined based on said location without the need of a third reference scatterer and its distance to MIMO receiver (200).

[0089] In this embodiment, two scatterers are present and both of them are resolvable at the MIMO receiver (200) side.

[0090] MIMO receiver (200) position may be calculated using below formula where MIMO transmitter (100) position is (Pt l,Pt 2) in 2-dimensional plane, AOD and AOA are denoted by adand aa, and the scatterer distances are denoted byXiand yt.

[0091] Conventional beam training methods may be used in beam training step. Referring to figure 6, total number of beams (510) and the beam indices of the transmitter and receiver are denoted by (N,M) and (n,m), respectively. In this system, the wireless channel between the MIMO transmitter (100) and MIMO receiver (200) is different for each beam pair (500) selection gn mwhere n=1 ,2, ... ,N and m=1 ,2,...,M. Therefore, the path losses and multipath components for the beam pair (500) of Bn mare different. Beam selection is done based on the received signal strength indicator (RSSI) value. MIMO transmitter (100) transmits a reference signal from each beam (510) serially in the time domain. Then, the MIMO receiver (200) measures the signal strength for each beam (510) within a certain period. Then, the MIMO receiver (200) reports the best beam pair (500) index based on the signal strength measurement results to the MIMO transmitter (100). Thus, the signal is transmitted from the beam pair (500) that provides the best signal quality. The scope of protection of the invention is specified in the attached claims and cannot be limited to those explained for sampling purposes in this detailed description. It is evident that a person skilled in the art may exhibit similar embodiments in light of the above-mentioned facts without drifting apart from the main theme of the invention.

Claims

CLAIMS1. A method suitable for determining location of a multiple input-multiple output (MIMO) receiver in a system comprising a MIMO transmitter (100) having a predetermined location where said MIMO transmitter (100) and said MIMO receiver (200) has non- line-of-sight (NLOS) channel condition therebetween and at least a scatterer (300) for reflecting signals between said MIMO receiver (200) and said MIMO transmitter (100) characterized in that comprising steps of: realizing beam training by the MIMO transmitter (100) and by the MIMO receiver (200), and determining a beam pair for communication;- by MIMO transmitter (100), transmitting angle of departure (AOD) of a signal transmitted using determined beam pair to MIMO receiver (200) and transmitting said predetermined location information of MIMO transmitter (100) to MIMO receiver (200); by MIMO receiver (200), determining angle of arrival (AOA) of a signal received using determined beam pair from MIMO transmitter (100); realizing monostatic sensing by MIMO receiver (200) and / or by MIMO transmitter (100) on the scatterer (300) that reflects signals transmitted through the determined beam pair and determining a distance eX between MIMO transmitter (100) and the scatterer (300); and a distance eY between MIMO receiver (200) and the scatterer (300);- by MIMO receiver (200) acquiring the distance eX, and the distance eY; determining the location of the MIMO receiver (200) using the distance eX, the distance eY, the location of MIMO transmitter (100), the AOA and the AOD.

2. The method according to claim 1 , characterized in that comprising the steps of:- realizing monostatic sensing by MIMO receiver (200) on the scatterer (300) that reflects signals transmitted through the determined beam pair and determining the distance eY between MIMO receiver (200) and the scatterer (300); by MIMO receiver (200) determining time of arrival (TOA) of the signal received from MIMO transmitter (100) through determined beam pair;- by MIMO receiver (200), calculating a propagation distance d (d) using said TOA;- by MIMO receiver (200), estimating a distance eX between the scatterer (300) and the MIMO transmitter (100) using formula d = eX + eY.

3. The method according to claim 1 , characterized in that comprising the steps of:- realizing monostatic sensing by MIMO transmitter (100) on the scatterer (300) that reflects signals transmitted through the determined beam pair and determining the distance eX between MIMO transmitter (100) and the scatterer (300); transmitting the distance eX to MIMO receiver (200); by MIMO receiver (200) determining time of arrival (TOA) of the signal received from MIMO transmitter (100) through determined beam pair;- by MIMO receiver (200), calculating a propagation distance d (d) using said TOA,- by MIMO receiver (200), estimating a distance eY between the scatterer (300) and the MIMO receiver (200) using formula d = eX + eY.

4. The method according to claim 1 , characterized in that comprising the steps of:- realizing monostatic sensing by MIMO receiver (200) on the scatterer (300) that reflects signals transmitted through the determined beam pair and determining the distance eY between MIMO receiver (200) and the scatterer (300);- realizing monostatic sensing by MIMO transmitter (100) on the scatterer (300) that reflects signals transmitted through the determined beam pair and determining the distance eX between MIMO transmitter (100) and the scatterer (300).

5. The method according to claim 1 , characterized in that comprising the steps of:- realizing monostatic sensing by MIMO transmitter (100) on at least a first scatterer (301 ) and at least a second scatterer (302) that reflects signals transmitted through the determined beam pair and determining at least a distance eX1 and at least a distance eX2 between MIMO transmitter (100) and the first scatterer (301 ) and the second scatterer (302) respectively,- transmitting the distance eX1 and the distance eX2 to MIMO receiver (200); realizing monostatic sensing by MIMO receiver (200) on one of the first scatterer (301 ) or the second scatterer (302) determining the distance eY between MIMO receiver (200) and the first scatterer (301 ) or the second scatterer (302); by MIMO receiver (200) determining time of arrival (TOA) of the signal received from MIMO transmitter (100) through determined beam pair and determining a distance d; determining which scatterer’s distance eY is determined by the MIMO receiver (200) using below formula ith scatterer = min (distance d- (distance xi-distance eY) by MIMO receiver, using the distance of determined scatterer to MIMO transmitter (100) as the distance eX for location determination.

6. The method according to claim 1 , characterized in that comprising the steps of:- realizing monostatic sensing by MIMO transmitter (100) on at least a first scatterer (301 ) and at least a second scatterer (302) that reflects signals transmitted through the determined beam pair and determining at least a distance eX1 and at least a distance eX2 between MIMO transmitter (100) and the first scatterer (301 ) and the second scatterer (302) respectively,- transmitting the distance eX1 and the distance eX2 to MIMO receiver (200);- if it is determined that there is more than one scatterer on determined beam pair, realizing monostatic sensing by MIMO receiver (200) on at least the first scatterer (301 ) and on at least the second scatterer (302) determining the distance eY1 and the distance eY2 between MIMO receiver (200) and the first scatterer (301 ) and the second scatterer (302) respectively; by MIMO receiver, determining location of the MIMO receiver by using distance eX1 and the distance eX2 considering the communication directional.

7. A system comprising a MIMO transmitter (100) having a predetermined location where said MIMO transmitter (100) and said MIMO receiver (200) has non-line-of-sight (NLOS) channel condition therebetween and at least a scatterer (300) for reflecting signals between said MIMO receiver (200) and said MIMO transmitter (100) wherein said system is configured to realize a method of claim 1 to 6 for determining location of a MIMO receiver (200).

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