Communication

FIELDS OF THE APPLICATION

[0001] The present application generally relates to wireless communication and in particular to a method to transmit the quantized information value in wireless communication, with reduced effective quantization error. The present application has a specific application but not limited to the mobile positioning in 3 GPP Long Term Evolution (LTE) system that is one of the candidates for the 4-th generation wireless system.

BACKGROUND

[0002] It is expected that location based services (LCS) will bring great convenience and new exciting services to subscribers of future mobile communication networks and therefore generate significant revenues to the operators. LCS requires the integration of wireless network infrastructure, mobile terminals, and a range of location-specific applications and content. The fundamental technology supporting LCS, however, is mobile terminal positioning.

[0003] There are mainly five mobile positioning techniques discussed in 3GPP standard body. They are methods based on cell-ID, assisted-GPS signal, angle-of-arrive (AoA) measurement, time-of-arrival (ToA) measurement and time-difference-of-arrival (TDoA) measurement (also called observed-time-difference-of-arrival (OTDoA)). Among them, OTDoA based positioning technique has been chosen by 3 GPP standard body as the solution in E- UTRAN LTE release 9. In OTDoA positioning solution as shown in Figure 1, the mobile terminal, or so-called user equipment (UE), measures the timing differences between arrival timing (t _t , l<i<N) of signals coming from N synchronized neighboring base stations (or so- called eNB as 3 GPP LTE terminology) and the arrival timing (t ₀ ) of signal coming from a reference base station (or reference eNB). These N+l timing differences are reported to the network via serving eNB of the UE. Given each reported timing difference t _t -t ₀ , the network can assume the UE's position is close to a hyperbolic curve (for two-dimensional positioning) or hyperbolic surface (for three-dimensional positioning) that is determined by the 2D/3D locations of the corresponding z ^' -th neighboring eNB and reference eNB and the propagation distance difference Δ _; . = c · (t _i -t ₀ ) assuming line-of-sight (LOS) propagation path, where c is the speed of light. Therefore, the best estimated UE position is the one that has the least square of error distances with respective to all N hyperbolic curves or surfaces.

[0004] The positioning error of OTDoA-based estimation can come from three sources:

• NLOS error: The propagation path from the eNB to UE is non-line-of-sight (NLOS), which causes longer propagation time than in the LOS condition. When this happens, Δ _; . = c · (t _i - t ₀ ) no longer accurately represents the difference of LOS distances between two eNBs; however, the network still assumes the LOS condition when calculating Δ _; . and applying it in the positioning estimation. In general, this additional time due to NLOS depends on terrestrial conditions and is therefore random and unknown to the network.

• Measurement error: due to the weakness of wireless signal strength and/or existence of noise, the measurements of signal arrival timing may result in a random shift from the true instance of the signal arrival.

• Quantization error in UE's report: according to the LTE standard, the timing difference t _t - 1 ₀ is reported to the network in the quantization form specified by RSTD (which stands for Reference Signal Time Difference). The reporting range of RSTD is defined from -15391 Ts to 15391 Ts with ITs resolution for absolute value of RSTD less or equal to 4096Ts and 5Ts for absolute value of RSTD greater than 4096Ts. RSTD refers to the timing difference, t _i - 1 ₀ , and one T _s equals to 1/(15000*2048) second. The mapping of measured quantity is shown in the table below.

Table 1 OTDOA measurement report mapping in LTE

[0005] Note that the OTDOA measurement report does not distinguish the different measurements that fall into the same one T _s resolution, where one T _s interval corresponds to about 10 meters of propagation distance. But such resolution range is big enough to cause incorrect floor identification in the three-dimensional mobile positioning, given that 3 meters is generally the height per floor. Different from NLOS error and measurement error that are caused by random factors in the practical system operation, quantization error as mentioned above comes from the standard specification and therefore should be avoided through an improvement of the standard itself.

[0006] One approach to reducing the quantization error is to redefine the mapping table with a much smaller resolution step. However, it is hard to tell how small the new resolution step should be sufficient at the time of standard specification, since its effectiveness on the overall positioning accuracy also depends on other factors, which could be different on a per-UE basis. In addition, if the effective resolution is predefined in the standard and the value is too small, a lengthy mapping table may consume more memory in eNB and UE as well as the more signaling overhead in the UE report.

SUMMARY

[0007] The above deficiencies and other problems associated with the conventional approaches for mobile positioning and corresponding data transmission are reduced or eliminated by the application disclosed below. In some embodiments, the application is implemented in an electronic device, and example electronic devices include a user equipment (e.g., a mobile phone and a tablet), and a network computer that is used as a server.

[0008] One aspect of the application is a mobile positioning method implemented at a user equipment. The user equipment is communicatively coupled to a plurality of base stations over one or more communication networks, and includes one or more processors and a memory that stores instructions implemented by the one or more processors. The mobile positioning method includes receiving signals from the plurality of base stations. Each of the plurality of base stations is associated with a respective arrival time for the respective signal to travel from the respective station to the user equipment. The mobile positioning method further includes calculating a timing difference between two of the arrival times of the signals, and the two of the arrival times are associated with a first base station and a second base station of the plurality of base stations, respectively. The mobile positioning method further includes magnifying the timing difference based on a quantization factor, quantizing the magnified timing difference according to at least one quantization resolution, and transmitting the quantized timing difference to a network computer. The network computer is configured to recover the timing difference by minifying the quantized timing difference based on the quantization factor, and apply a positioning method to identify a position of the user equipment with respect to at least the first and second base stations based on the recovered timing difference.

[0009] Another aspect of the application is a use equipment that includes one or more processors, and memory having instructions stored thereon, which when executed by the one or more processors cause the processors to perform operations to implement the above mobile positioning method.

[0010] Another aspect of the application is a non-transitory computer-readable medium, having instructions stored thereon, which when executed by one or more processors cause the processors to perform operations to implement the above mobile positioning method. [0011] In accordance with another aspect of the application, a mobile positioning method is implemented at a network computer side. A network computer includes one or more processors, and memory having instructions stored thereon, which when executed by the one or more processors cause the processors to perform operations to implement this mobile positioning method. The mobile positioning method includes receiving from a user equipment a plurality of quantized timing differences. The user equipment is configured to obtain the plurality of quantized timing differences at least by magnifying a plurality of timing differences associated with a plurality of base stations according to a quantization factor. The mobile positioning method further includes minifying the plurality of quantized timing differences based on the quantization factor to recover the plurality of timing differences associated with the base stations. The mobile positioning method further includes applying a positioning method to identify a position of the user equipment based on the plurality of recovered timing differences associated with the base stations.

[0012] Various advantages of the present invention would be apparent in light of the descriptions below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 depicts exemplary OTDOA measurements and report involving multiple eNBs and UE.

[0014] Figure 2 depicts the OTDOA positioning performances on horizontal 2D surface and elevation for different quantization factors according to some embodiments of the present application.

[0015] Figure 3 depicts a flow chart for transmission of the quantized value between two entities according to some embodiments of the present application.

[0016] Figure 4 is a flow chart of a mobile positioning method according to some embodiments of the present application.

[0017] Figure 5 is a block diagram of an exemplary first entity device that is configured to transmit a quantized information value in accordance with some embodiments.

[0018] Figure 6 is a block diagram of an exemplary second entity device that is configured to receive and further process a quantized information value in accordance with some embodiments. DETAILED DESCRIPTION

[0019] The present application is directed to a method to reduce the effective

quantization error without changing the measurement mapping table currently defined in LTE. Instead, a new quantization factor is shared between UE and network. The UE magnifies the measurement to be reported by multiplying it with the quantization factor before applying the quantization according to the LTE-defmed mapping table. After receiving the UE report containing the quantized timing difference, the network minifies the quantized timing difference by dividing it with the quantization factor.

[0020] Even though the claimed method is designed for UE report in mobile positioning, the same principle can be used in any wireless messaging system containing quantization quantities for other purposes.

[0021] These and other implementations and examples of this design in software and hardware are described in greater details in the attached drawings, the detailed description and the claims.

[0022] Denote the quantization of a value x as a function Q{X) . The math formula of the quantization operation can be represented as x = ζ)(χ) + ε _χ , where ε _χ is the quantization error with < R and R is the quantization resolution. Following the same formula, the quantization

1 ε of k - x is k - x = Q k - x)+ ε _1α , where |¾| < R . This is equivalent to x =— - Q(k - x)-\—— with k k . In other words, if the quantization factor k is multiplied by the value x before the

quantization and it is also used to divide the quantization result, the effective quantization error is no larger than of the original quantization resolution R. For k>l, the effective

quantization error is reduced by k times compared with the direct quantization of x.

[0023] To apply the above mathematic principle to the quantization and report in mobile positioning application, a quantization factor, k (k>l), needs to be shared between UE and the network.

• On UE side: each measured timing difference is magnified by k times by multiplying quantization factor k; the magnified value is quantized according to the pre-defined mapping table above; the quantization result is then reported to the network via signaling. • On network side: after receiving the report from UE, the network minifies each quantized timing difference in the report by dividing it with the quantization factor k; the division result is treated as the measured timing differences and is applied in positioning algorithm.

[0024] The above operations assume the quantization factor is no less than 1. In some embodiments, the quantization factor can be a positive number less than 1. In this case, the multiplication on the UE side and division on network side should be changed accordingly: the quantization factor k (0<k<l) is used to divide the measured timing differences on the UE side and used to multiply the reported values on the network side.

[0025] The quantization factor k can be a fixed value specified by the standard.

Alternatively, this parameter may be configurable on a per-UE basis. This is because:

• According to the LTE standard, the quantization resolution R is one T _s if UE is at the location such that the arrival timing and to satisfy \k · or equivalently I 4096

t. -t ₀ ≤ T _s , otherwise R is 5T _S . Therefore even though larger value of k can

k

effectively reduce the quantization error, it also reduce the UE position range, in which the UE's quantization resolution is R=T _S instead of R=5T _S . So, for the given UE's location, the network can adjust quantization factor k so as to get the minimum RJk.

• As LTE evolves to later release, the mobile positioning accuracy could be required for further improvement, which may need the capability to have larger quantization factor k. So it is not convenient to specify it as a fix value in the standard.

[0026] Figure 2 depicts the simulated OTDOA positioning performances, in terms of

CDF (which stands for cumulative distribution function) vs. error distance, on both horizontal 2D surface and elevation. The quantization factors used in the simulation include {1,2,4,8}, so the corresponding effective quantization resolutions are R={T _S , T _s /2, T _s /4, T _s /8} . The simulation assumes no measurement error and NLOS error. It is shown that the larger quantization factor brings significant performance improvements.

[0027] Even though the above-mentioned method to transmit a quantized value from UE to network is described in context of mobile positioning, the same principle can be applied in any operation that transmits the quantized information from one entity to another entity, for example, from network node to UE. As shown in Figure 3, when some information value is to be transmitted from the first entity to the second entity in the quantized format,

• One quantization factor is shared between the first entity and the second entity;

• The first entity does the following operations: o magnify the information value by multiplying the information value by the quantization factor; o quantize the magnified information value; o transmit the quantized information value to the second entity;

• The second entity does the following operations: o minify the received quantization value by dividing the received quantization value with the quantization factor.

[0028] In implementation, the above described methods and their variations may be implemented as computer software instructions or firmware instructions. Such instructions may be stored in an article with one or more machine-readable storage devices connected to one or more computers or integrated circuits or digital processors such as digital signal processors and microprocessors. In a communication system of 3GPP LTE, the claimed method and related operation flow and process may be implemented in form of software instructions or firmware instructions for execution by a processor in the transmitter and receiver or the transmission and reception controller. In operation, the instructions are executed by one or more processors to cause the transmitter and receiver or the transmission and reception controller to perform the described functions and operations.

[0029] Figure 4 is a flow chart of a mobile positioning method 400 in accordance with some embodiments of the application. Specifically, in some implementations, mobile positioning method 400 is implemented at a user equipment that is communicatively coupled to a plurality of base stations over one or more communication networks. In a specific example, the communication networks include a communication system implemented based on the Third Generation Partnership Project and Long-Term Evolution (3GPP LTE). Further, as shown in Figure 1 , mobile positioning method 400 could be applied to identify a position of the user equipment (e.g., the UE) with respect to the plurality of base stations (e.g., the eNBs in Figure 1 including neighboring eNBs 1, 2, ... and N, serving eNB and Reference eNB). [0030] The UE receives (402) signals from the plurality of base stations. Each of the plurality of base stations is associated with a respective arrival time for the respective signal to travel from the respective base station to the UE. For example, the UE receives a signal from a neighboring base station. An arrival time relates to the time for the signal to travel from the neighboring base station to the UE over the distance between them. Likewise, a reference base station transmits a reference signal to the UE, and a reference arrival time relates to the time for the reference signal to travel from the reference base station to the UE over the distance between the reference base station and the UE.

[0031] After receiving the signals, the UE calculates (404) a timing difference between two of the arrival times of the signals. The two of the arrival times are associated with a first base station and a second base station of the plurality of base stations, respectively. In some implementations, the signals are transmitted from the plurality of base stations to the UE in a synchronous manner. The timing difference is calculated directly from the arrival times of the signals. Alternatively, in some implementations, the signals from the base stations are independent from each other. For each of the base stations, a respective arrival time is recorded with reference to an emission time. The respective emission time has to be considered during the course of calculating the timing difference between the two of the arrival times of the signals.

[0032] In some embodiments, the first and second base stations are two distinct neighboring base stations. The timing difference is associated with a prorogation distance difference A _y =c-(trt _j ), where c is the speed of light, and and t _j are the arrival times associated with the z ^' -th and y ^' -th neighboring base stations, respectively.

[0033] Alternatively, in some embodiments, one of the first and second base stations includes the reference base station, and the other of the first and second base stations includes one of the neighboring base stations. The timing difference is measured for the one of the neighboring base station with reference to that of the reference base station. As explained above, the timing difference is associated with a prorogation distance difference Δ _; . = c ^■ (t _{ - t ₀ ) , where c is the speed of light, and and to are the arrival times associated with the z ^' -th neighboring base station and the reference base station. Further, it is noted that in some implementations, the UE calculates a plurality of timing differences from the arrival times associated with the plurality of base stations, and the plurality of timing differences is calculated for each of the neighboring base stations with respect to the arrival time of the reference base station. [0034] The UE magnifies (406) the calculated timing difference based on a quantization factor. Optionally, the quantization factor is set forth by the UE. As explained above, in some embodiments, the magnifying the timing difference based on the quantization factor includes multiplying the timing difference by the quantization factor, and the quantization factor is larger than 1. Alternatively, in some embodiments, the magnifying the timing difference based on the quantization factor includes dividing the timing difference by the quantization factor, and the quantization factor is smaller than 1.

[0035] In some implementations, a characteristic of the UE is determined and used in selection of the quantization factor. Selection of the quantization factor is optionally completed either at the user equipment or at the network computer. In some embodiments, the UE adjusts the quantization factor according to the determined characteristic, such that the magnitude of the magnified timing difference does not exceed a predetermined value. In a specific example, the predetermined value is equal to 15391 · ¾, where Ts represents the time interval of one OFDM sample and is equal to 1/(15000* 2048) second. Optionally, Ts is also used as a quantization resolution to digitize data transmitted between the base stations and the UE.

[0036] In some embodiments, the characteristic of the UE is associated with a preliminary equipment location that is roughly estimated for the UE. Further, in some embodiments, the preliminary equipment location of the UE is estimated by the network computer, and used by the network computer to determine the quantization factor that is then provided to the UE. If the estimated preliminary equipment location could lead to a relatively large timing difference that goes beyond the predetermined value, the quantization factor is reduced to control the magnified timing difference below the predetermined value.

Alternatively, if the estimated preliminary equipment location leads to a relatively small timing difference, the quantization factor could be increased as long as the magnified timing difference does not exceed the predetermined value.

[0037] It is noted that in some implementations, the network computer can roughly estimate the timing difference according to the location of the serving base station associated with the user equipment. Such estimated timing difference is used only to select the quantization factor, but not to substitute the timing difference measured and reported by the user equipment. In this situation, the preliminary equipment location does not need to be known as part of the characteristic of the UE. [0038] The UE quantizes (408) the magnified timing difference according to at least one quantization resolution. In some embodiments, the at least one quantization resolution includes a first quantization resolution. The UE determines that the magnified timing difference has a magnitude within a first predetermined range, and quantizes the magnified timing difference by dividing the magnified timing difference by the first quantization resolution. In an example, the first predetermined range is between 0 and 4096-Ts, and the first quantization resolution is equal to Ts, where Ts is equal to time duration of one sample interval.

[0039] Further, in some embodiments, the at least one quantization resolution further includes a second quantization resolution. The UE determines that the magnified timing difference has a magnitude exceeds the first predetermined range, and quantizes the magnified timing difference by dividing the magnified timing difference by the second quantization resolution that is scaled based on the first quantization resolution. In an example, the second quantization resolution is equal to 5-Ts. When the magnified timing difference is larger than 4096-Ts, the magnified timing difference is divided by 5Ts for quantization.

[0040] The UE transmits (410) the quantized timing difference to a network computer.

Optionally, the network computer is associated with a serving base station that is selected from the neighboring base stations, the reference base station and a base station independent of the neighboring and reference base stations. Optionally, the network computer is independent of any base station. The network computer is configured to recover the timing difference by minifying the quantized timing difference based on the quantization factor that is used by the user equipment to magnify the timing difference, and apply a positioning method to identify a position of the UE with respect to at least the first and second base stations based on the recovered timing difference.

[0041] In some embodiments, the quantization factor used to magnify the timing difference at the UE is originally provided to the UE by the network computer, and does not have to be transmitted from the UE back to the network computer. Rather, the network computer retrieves the quantization factor from its own memory during the course of recovering the timing difference. Alternatively, in some situations, the quantization factor is set forth by the user equipment, and the quantization factor is transmitted from the UE to the network computer in conjunction with the quantized timing difference. [0042] The recovered timing difference could be used to calculate the difference between a first distance and a second distance that are measured from the first and second base stations to the UE, respectively. In accordance with the positioning method, such a difference between the first and second distances is applied in identification of the position of the UE with respect to at least the first and second base stations. Further, given that the locations of the plurality of base stations are normally known, the relative position derived from the recovered timing difference could be used to identify an absolute location of the UE on a map (e.g., its longitude and altitude).

[0043] In some embodiments, the network computer collects two or more timing differences for the purposes of identifying the relative position of the UE with respect to the plurality of base stations and the absolute location of the UE on a map. For example, in some embodiments, three or more timing differences are obtained and transmitted to the network computer for identifying a two-dimensional (2D) location of a UE on a map. Such a

determination of the 2D location of the UE is based on at least four arrival times associated with four distinct base stations. In some embodiments, four or more timing differences are obtained and transmitted to the network computer for identifying a three-dimensional (3D) location of a UE. Such a determination of the 3D location of the UE is based on at least five arrival times associated with five distinct base stations.

[0044] As explained above with reference to Figure 2, the quantization error is between

0 and Ts for a timing difference (magnified or not) if transmitted directly from the UE to the network computer, and could increase to 5 · T _s if a scaled quantization resolution of 5Ts is used to quantize the corresponding timing difference. When the magnified timing difference is minified at the network computer side, the quantization error of the corresponding recovered timing difference is reduced according to the quantization factor. Thus, the accuracy of the recovered timing difference is enhanced in view of the situation in which the timing difference is quantized and transmitted without magnification.

[0045] One of those skilled in the art knows that mobile positioning method 400 shown in Figure 4 is merely an example of a method for transmitting a quantized information value with enhanced data accuracy. In some implementations, such a data transmission method is implemented at a first entity device that is not limited to a UE. A quantized information value and a quantized factor are processed for transmission to a second entity device that is not limited to a network computer. Optionally, the quantized information value is not limited to a timing difference. For example, the first entity device could be a network computer, while the second entity device is a user equipment. In accordance with the data transmission method, the first entity device magnifies an information value based on a quantization factor, and quantizes the magnified information value according to at least one quantization resolution. Then, the quantized information value is transmitted to the second entity device in conjunction with the quantization factor. The second entity device is configured to recover the information value by minifying the quantized information value based on the quantization factor.

[0046] Alternatively, in some embodiments, a mobile positioning method is

implemented at a network computer side. The network computer is configured to receive from a user equipment a plurality of quantized timing differences. The user equipment is configured to obtain the plurality of quantized timing differences at least by magnifying a plurality of timing differences associated with a plurality of base stations according to a quantization factor. The plurality of quantized timing differences are then minified at the network computer based on the quantization factor to recover the plurality of timing differences associated with the base stations. The network computer applies a positioning method to identify a position of the user equipment based on the plurality of recovered timing differences associated with the base stations. In some implementations, the quantization factor is set forth by the user equipment, and the network computer is configured to receive the quantization factor from the user equipment in conjunction with the plurality of quantized timing differences. In some implementations, the network computer is configured to provide the quantization factor to the user equipment for magnifying the plurality of timing differences associated with the base stations, and in accordance with the mobile positioning method, the quantization factor is retrieved from a memory of the network computer during the course of recovering the plurality of timing differences associated with the base stations.

[0047] Figure 5 is a block diagram of an exemplary first entity device 500 that is configured to transmit a quantized information value in accordance with some embodiments. In a specific example, first entity device 500 includes a user equipment that implements a mobile positioning method involving transmission of quantized timing difference data. In some implementations, first entity device 500 at least includes one or more processors 510 (e.g., central processing units and baseband processor) and a memory 520 for storing data, programs and instructions for execution by one or more processors 510. In some implementations, first entity device 500 further includes one or more communication interfaces 530, an input/output (I/O) interface 540, and one or more communication buses 550 that interconnect these components.

[0048] In some embodiments, I/O interface 540 includes an input unit 542 and a display unit 544. Examples of input unit 542 include a keyboard, a mouse, a touch pad, a game controller, a function key, a trackball, a joystick, a microphone, a camera and the like.

Additionally, display unit 544 displays information that is inputted by the user or provided to the user for review. Examples of display unit 544 include, but are not limited to, a liquid crystal display (LCD) and an organic light-emitting diode (OLED) display. In some implementations, input unit 542 and display unit 544 are integrated on a touch-sensitive display that displays a graphical user interface (GUI).

[0049] In some embodiments, communication buses 550 include circuitry (sometimes called a chipset) that interconnects and controls communications between system components. In some embodiments, communication interfaces 530 further include a receiver 532 and a transmitter 534.

[0050] In some embodiments, memory 520 includes high-speed random access memory, such as DRAM, SRAM, DDR RAM or other random access solid state memory devices; and optionally includes non-volatile memory, such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid state storage devices. In some embodiments, memory 520 includes one or more storage devices remotely located from the one or more processors 510. In some embodiments, memory 520, or alternatively the non-volatile memory device(s) within memory 520, includes a non-transitory computer readable storage medium.

[0051] In some embodiments, memory 520 or alternatively the non-transitory computer readable storage medium of memory 520 stores the following programs, modules and data structures, instructions, or a subset thereof:

• Operating System 501 that includes procedures for handling various basic system

services and for performing hardware dependent tasks;

• I/O interface module 502 that includes procedures for handling various basic input and output functions through one or more input and output devices, wherein I/O interface module 502 further includes an interface display module that controls displaying of a graphical user interface;

• Communication module 503 that is used for connecting first entity device 500 to other computational devices (e.g., servers and client devices), via one or more network communication interfaces 550 (wired or wireless) and one or more communication networks, such as the Internet, other wide area networks, local area networks, metropolitan area networks, and so on;

• Data quantization and transmission module 504 that is configured to magnify an

information value (e.g., a timing difference) based on a quantization factor, quantize the magnified information value and transmit the quantized information value to a second entity device; and

• Database 505 that stores one or more of quantization factors 505 A, quantization

resolutions 505B and measurement report mapping 505C.

[0052] In some embodiments, data quantization and transmission module 504 at least includes a quantization factor determination module 504 A configured to determine the quantization factor. Optionally, the quantization factor is extracted locally from database 505. The quantization factor is then transmitted to the second entity device in conjunction with the quantized information value. Optionally, the quantization factor has been provided by the second entity device that is configured to receive the quantized information value. The second entity device is also configured to retrieve the quantization factor from its own memory during the course of recovering the timing difference.

[0053] In some implementations, first entity device 500 includes a UE that provides quantized timing difference for identifying its own position with respect to a plurality of base stations. First entity device 500 further includes a mobile positioning module 506. First entity device 500 is configured to receive signals from the plurality of base stations. Each of the plurality of base stations is associated with a respective arrival time for the respective signal to travel from the respective station to the user equipment. Optionally, the respective arrival time is associated with a distance between the respective station and the user equipment. Mobile positioning module 506 obtains the arrival times associated with the base stations, and calculates at least one timing difference between two of the arrival times of the signals. The two of the arrival times are associated with a first base station and a second base station of the plurality of base stations, respectively. The calculated timing difference is magnified and quantized by data quantization and transmission module 504 prior to being transmitted to a second entity device.

[0054] More details on functions of mobile positioning module 506 and data

quantization and transmission module 504 are explained above with reference to Figures 1-4.

[0055] Figure 6 is a block diagram of an exemplary second entity device 600 that is configured to receive and further process the quantized information value in accordance with some embodiments. In a specific example, second entity device 600 includes a network computer that is configured to recover one or more timing differences associated with a plurality of base stations and a UE. In accordance with the recovered timing differences, the network computer is configured to identify a position of the UE with respect to a subset of the base stations.

[0056] In some implementations, second entity device 600 at least includes one or more processors 610 (e.g., central processing units) and a memory 620 for storing data, programs and instructions for execution by one or more processors 610. In some implementations, second entity device 600 further includes one or more communication interfaces 630, an input/output (I/O) interface 640, and one or more communication buses 650 that interconnect these components.

[0057] In some embodiments, I/O interface 640 includes an input unit 642 and a display unit 644. Examples of input unit 642 include a keyboard, a mouse, a touch pad, a game controller, a function key, a trackball, a joystick, a microphone, a camera and the like.

Additionally, display unit 644 displays information that is inputted by the user or provided to the user for review. Examples of display unit 644 include, but are not limited to, a liquid crystal display (LCD) and an organic light-emitting diode (OLED) display. In some implementations, input unit 642 and display unit 644 are integrated on a touch-sensitive display that displays a graphical user interface (GUI).

[0058] In some embodiments, communication buses 650 include circuitry (sometimes called a chipset) that interconnects and controls communications between system components. In some embodiments, communication interfaces 630 further include a receiver 632 and a transmitter 634. [0059] In some embodiments, memory 620 includes high-speed random access memory, such as DRAM, SRAM, DDR RAM or other random access solid state memory devices; and optionally includes non-volatile memory, such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid state storage devices. In some embodiments, memory 620 includes one or more storage devices remotely located from the one or more processors 610. In some embodiments, memory 620, or alternatively the non-volatile memory device(s) within memory 620, includes a non-transitory computer readable storage medium.

[0060] In some embodiments, memory 620 or alternatively the non-transitory computer readable storage medium of memory 620 stores the following programs, modules and data structures, instructions, or a subset thereof:

• Operating System 601 that includes procedures for handling various basic system

services and for performing hardware dependent tasks;

• I/O interface module 602 that includes procedures for handling various basic input and output functions through one or more input and output devices, wherein I/O interface module 602 further includes an interface display module that controls displaying of a graphical user interface;

• Communication module 603 that is used for connecting second entity device 600 to other computational devices (e.g., servers and client devices), via one or more network communication interfaces 650 (wired or wireless) and one or more communication networks, such as the Internet, other wide area networks, local area networks, metropolitan area networks, and so on;

• Quantization Factor Determination Module 604 that is configured to determine a

quantization factor; and

• Quantized Data Recovery Module 605 that is configured to obtain a quantized

information value (e.g., a quantized timing difference) and the corresponding

quantization factor, and recover an information value therefrom.

[0061] In some implementations, second entity device 600 includes a network computer that receives one or more quantized timing differences associated with a UE and identifies a position of the UE with respect to a plurality of base stations. In some implementations, the quantization factor is set forth by first entity device, and transmitted to second entity device 600 in conjunction with the quantized timing difference. In accordance with the received quantization factor, quantization factor determination module 604 is configured to identify and provided to module 605 this received quantization factor. Alternatively, in some

implementations, quantization factor determination module 604 is configured to determine the quantization factor, and provide the quantization factor to first entity device for quantization. During the course of recovering the timing difference, second entity device 600 is configured to retrieve the quantization factor at quantization factor determination module 604.

[0062] Second entity device 600 further includes a mobile positioning module 605.

Quantized data recovery module 604 of second entity device 600 is configured to minify a quantized timing difference using a quantization factor that has been either received from first entity device 500 in conjunction with the quantized timing difference or determined by second entity device 600 and then configured to the first entity device 500. In accordance with a positioning method, mobile positioning module 605 is configured to identify a relative position of the UE with respect to at least two of the base stations (e.g., a first base station and a second base station) based on at least the recovered timing difference. Under some circumstances, mobile positioning module 606 obtains more than one recovered timing differences from quantized data recovery module 605, and could identify more than one relative position with respect to a subset of the base stations for the purposes of deriving an absolution position of the UE on a map.

[0063] More details on functions of mobile positioning module 605 and data quantization and transmission module 604 are explained above with reference to Figures 1-4.