Network receiver for receiving high-speed transmitted signals

Abstract

Calculating the phase difference of the OFDM symbols of the PUCCH from the OFDM symbols of the first and second DM-RSs, the OFDM symbols of the second and third DM-RSs, and the OFDM symbols of the first and third DM-RSs; correlating the OFDM symbols across all DM-RSs; determining the Doppler shift reported to layer 2; compensating the channel estimation results and data symbols with the Doppler shift; performing a first-level phase correction for the PUSCH by correcting the phase on the output samples of the IDFT from the Doppler shift received from layer 2; measuring the phase deviation on the output of the first-level phase correction; accumulating the measured phase deviation and the received Doppler shift; reporting the accumulated phase correction to layer 2; and performing a second-level phase correction. A technique for receiving PUSCH and PUCCH transmitted by a high-speed transmitter is provided.

Description

Technical Field

[0001] In some embodiments, the subject matter herein generally relates to mobile wireless communication systems, and more specifically relates to a network-side receiver that receives wireless signals transmitted from a high-speed moving mobile type device. Background Art

[0002] The introduction and rapid expansion of digital wireless networks in the 1990s marked the beginning of the wireless revolution. Commercial wireless providers transitioned from analog to digital wireless technologies that enable more efficient utilization of radio resources, which has led to an increase in wireless voice traffic and a dramatic growth in wireless digital data services. Subsequently, a paradigm shift from wired to wireless occurred. Wireless computer networks, wireless Internet, and the like are now expected to be accessible in substantially all locations.

[0003] Wireless users may include conventional mobile phone users and portable computing devices such as laptop computers or tablet computers. The distinction between modern mobile phones and personal computing devices has become difficult to draw. Modern mobile phones have evolved into personal computing devices that host applications or services for calling, texting, messaging, e-mail, video recording and viewing, live streaming, and applications typically found on personal or business computing devices, such as word processing, spreadsheets, and the like.

[0004] Wireless access is available in substantially all metropolitan areas. In addition, it has become common sense for wireless users to access their devices wherever they go, unless there are specific restrictions. For example, users expect wireless access to be available while they are traveling by car, bus, ship, train, or the like.

[0005] In order to establish and maintain wireless connectivity between mobile devices and wireless devices, including base stations or eNBs (electronic network receivers), the base station or eNB must be able to decode the physical uplink shared channel (PUSCH) and the physical uplink control channel (PUCCH).

[0006] Some land-based modes of transport offer travel at high speeds or speed rates (for example, the Shinkansen can travel at speeds exceeding 350 kph or 217 mph). [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] Conventional wireless network receivers (e.g., eNBs) may be unable to perform push and push operations due to high phase deviations caused by Doppler shifts in signals transmitted in high-speed environments. While WiFi services may be available on some modes of transport, access is limited and requires a mobile device with WiFi capabilities.

[0008] Thus, there is a need for solutions that enable base stations or network receivers such as eNBs to receive signals transmitted while transmitting devices are moving at high speeds or rate-of-speed. [Means for solving the problem]

[0009] In one general aspect, a method is provided for decoding a physical uplink shared channel (PUSCH) and a physical uplink controlled channel (PUCCH) received by a receiver in a high-speed environment. The method may include calculating the phase difference of the OFDM symbols of the PUCCH from the OFDM symbols of the first DM-RS and the OFDMA symbols of the second DM-RS of the PUCCH, the OFDMA symbols of the second DM-RS and the OFDM symbols of the third DM-RS of the PUCCH, and the OFDM symbols of the first DM-RS and the third DM-RS of the PUCCH, which are consecutive demodulated reference signal (DM-RS) symbols of the PUCCH received by the receiver. The method may also include correlating the OFDM symbols of the first DM-RS and the second DM-RS, the second DM-RS and the third DM-RS, and the OFDM symbols of the first DM-RS and the third DM-RS. Furthermore, the method may include determining a Doppler shift proportional to the phase difference across all DM-RS symbols in the channel. The method may also include reporting the Doppler shift to Layer 2 (L2) of the protocol stack. In addition, the method may include compensating the channel estimation results and data symbols with the Doppler shift. The method may also include equalizing and demodulating the PUCCH. Furthermore, the method may include performing a first level of phase correction on the PUCCH received by the receiver by correcting the phase on the output samples of the inverse discrete Fourier transform (IDFT) from the Doppler shift received from Layer 2. The method may also include measuring the phase deviation on the output of the first level of phase correction and accumulating the measured phase deviation on the output of the first level of phase correction and the Doppler shift received from Layer 2 to obtain an accumulated phase correction. The method may also include reporting the accumulated phase correction to Layer 2. In addition, the method may include performing a second level of phase correction according to the measured phase deviation of the output of the first level of phase correction, and demodulating the PUSCH.Other embodiments of this aspect include a corresponding computer system, apparatus, and a computer program recorded on one or more computer storage devices, each configured to perform the actions of the method.

[0010] An implementation may include one or more of the following features: A method for measuring the phase deviation on the output of a first-level phase correction, which involves moving all quadrature amplitude modulation (QAM) symbols to the first quadrant by applying phase shifts of -π / 4, -π / 2, and -π / 3 radians to symbols in the second, third, and fourth quadrants, respectively. The method may also include calculating the difference between the average phase of the QAM symbols and the expected average phase of π / 4 radians or 45 degrees. A method for performing a first-level phase correction on a PUSCH, which involves receiving a Doppler shift reported by Layer 1 to Layer 2, and if the value of the Doppler shift received from Layer 2 is zero, performing a second-level phase correction twice. A method for measuring the phase deviation among all DM-RS symbols. Implementations of the described techniques may include hardware, methods, processes, or computer media.

[0011] In other common aspects, devices are provided for decoding physical uplink shared channels (PUSCH) and physical uplink controlled channels (PUCCH) received by receivers in high-speed environments.

[0012] The device calculates the phase difference of the OFDM symbols of PUCCH from the first DM-RS OFDM symbol and the second DM-RS OFDMA symbol of PUCCH, the second DM-RS OFDMA symbol and the third DM-RS OFDM symbol of PUCCH, and the first DM-RS and third DM-RS OFDM symbols of PUCCH, correlates the first DM-RS and second DM-RS, the second DM-RS and third DM-RS OFDM symbols, determines the Doppler shift proportional to the phase difference across all DM-RS symbols in the channel, and reports the Doppler shift to layer 2 of the protocol stack. The system may include a processor circuit configured to execute a number of instructions and coupled to memory in order to perform: equating and demodulating the PUCCH; performing a first level of phase correction on the PUCCH received by the receiver by compensating the channel estimation result and data symbols with Doppler shift; correcting the phase on the output samples of the inverse discrete Fourier transform (IDFT) from the Doppler shift received from Layer 2; measuring the phase deviation on the output of the first level of phase correction; accumulating the measured phase deviation on the output of the first level of phase correction and the Doppler shift received from Layer 2 to obtain an accumulated phase correction; reporting the accumulated phase correction to Layer 2; performing a second level of phase correction according to the measured phase deviation on the output of the first level of phase correction; and demodulating the PUCCH. Other embodiments of this aspect include a corresponding computer system and a computer program recorded on one or more computer storage devices, each configured to perform the actions of the device.

[0013] An implementation may include one or more of the following features: a device that measures the phase deviation on the output of a first-level phase correction, thereby moving all quadrature amplitude modulation (QAM) symbols to the first quadrant by applying phase shifts of -π / 4, -π / 2, and -π / 3 radians to symbols in the second, third, and fourth quadrants, respectively; a device in which the processor circuitry is further configured to execute a number of instructions to perform the calculation of the difference between the average phase of the QAM symbols and the expected average phase of π / 4 radians or 45 degrees; a device in which the second-level phase correction is performed twice if the value of the Doppler shift received from Layer 2 is zero; a device in which performing the first-level phase correction on PUSCH involves receiving the Doppler shift reported to Layer 2 by Layer 1; and a device in which the phase deviation is measured between all DM-RS symbols. Implementations of the described technology may include hardware, methods or processes, or computer media.

[0014] In other general aspects, a communication system is provided. The communication system includes a mobile device configured to transmit a physical uplink shared channel (PUSCH) and a physical uplink controlled channel (PUCCH) in a high-speed environment, and an eNodeB. eNodeB calculates the phase difference of the OFDM symbols of PUCCH from the first DM-RS OFDM symbols and second DM-RS OFDMA symbols of PUCCH, the second DM-RS OFDMA symbols and third DM-RS OFDM symbols of PUCCH, and the first DM-RS and third DM-RS OFDM symbols of PUCCH, correlates the first DM-RS and second DM-RS, the second DM-RS and third DM-RS OFDM symbols, and determines the Doppler shift proportional to the phase difference across all DM-RS symbols in the channel. The system is configured to perform the following: report the Doppler shift to Layer 2 of the protocol stack; compensate the channel estimation results and data symbols with the Doppler shift; equalize and demodulate the PUCCH; perform a first level of phase correction on the PUSCH received by the receiver by correcting the phase on the output samples of the inverse discrete Fourier transform (IDFT) from the Doppler shift received from Layer 2; measure the phase deviation on the output of the first level of phase correction; accumulate the first level of phase correction with the measured phase deviation to obtain the accumulated phase correction; report the accumulated phase correction to Layer 2; perform a second level of phase correction according to the measured phase deviation on the output of the first level of phase correction; and demodulate the PUSCH. Other embodiments of this aspect include a corresponding computer system and a computer program recorded on one or more computer storage devices, each configured to perform the actions of the method.

[0015] An implementation may include one or more of the following features: A communication system in which measuring the phase deviation on the output of a first-level phase correction moves all quadrature amplitude modulation (QAM) symbols to the first quadrant by applying phase shifts of -π / 4, -π / 2, and -π / 3 radians to symbols in the second, third, and fourth quadrants, respectively; a communication system in which the eNodeB is further configured to calculate the difference between the average phase of the QAM symbols and the expected average phase of π / 4 radians or 45 degrees; a communication system in which the second-level phase correction is performed twice if the Doppler shift received from Layer 2 is zero; a communication system in which performing the first-level phase correction on PUSCH is received by Layer 1 to Layer 2; a communication system in which the phase deviation is measured between all DM-RS symbols. Implementations of the described techniques may include hardware, methods or processes, or computer media. [Brief explanation of the drawing]

[0016] In the following drawing:

[0017] Figure 1 illustrates a communication link between a mobile device and a network device according to one embodiment.

[0018] Figure 2 illustrates a generalized PUSCH receiving chain.

[0019] Figure 3 illustrates a generalized PUCCH receiving chain.

[0020] Figure 4 shows the QPSK constellation diagram.

[0021] Figure 5 shows the 16 QAM constellation diagram.

[0022] Figure 6 illustrates a PUCCH receiver processing chain according to several embodiments.

[0023] FIG. 7 illustrates a PUSCH receiver processing chain in accordance with some embodiments,

[0024] FIG. 8 is a flowchart of an example process for receiving a PUCCH transmitted from a high-speed mobile device,

[0025] FIG. 9 is a flowchart of an example process for receiving a PUSCH transmitted from a high-speed mobile device. DETAILED DESCRIPTION OF EMBODIMENTS

[0026] FIG. 1 illustrates a communication link between a mobile device and a network device. Network device 102, which may be a base station (eNB), an access point or the like, transmits a signal 106 to mobile device 104 and receives a signal 108 transmitted by mobile device 104. The signal 106 may be referred to as a downlink (DL) signal, and the signal 108 may be referred to as an uplink (UL) signal. Mobile device 104 receives the signal 106 from network device 102 and transmits the signal 108 to network device 102.

[0027] There are notable differences between UL and DL signals in wireless communication systems such as LTE. These differences include transmission and multiple access schemes that can result in different physical layer processing. For example, UL may be based on Single-Carrier Frequency Division Multiple Access (SC-FDMA), and DL may be based on Orthogonal Frequency Division Multiple Access (OFDMA). SC-FDMA modulation can have a lower peak-to-average power ratio, which can lead to lower cost amplifiers and lower power usage. User data is modulated onto a single-carrier modulation format and may be modulated using higher-order modulation such as Quadrature Phase Shift Keying (QPSK), 16 Quadrature Amplitude Modulation (QAM), or 64 QAM. In 16 QAM, a carrier may be modulated into any of 16 different phase and amplitude states, and in 64 QAM, a carrier may be modulated into any of 64 different phase and amplitude states.

[0028] The uplink signal may not have a dedicated synchronization signal. The uplink frame can be synchronized using a PUCCH demodulation reference signal (DM-RS). The following description focuses on PUSCH and PUCCH. PUSCH carries user data and control signal data. The control data information may be multiplexed with user data before a discrete Fourier transform (DFT) spreading module in an uplink SC-FDMA physical layer.

[0029] Figure 2 illustrates a generalized PUSCH receive chain. The PUSCH signal 202 is received at 204. At 204, the signal is equalized, and an inverse discrete Fourier transform (IDFT) is performed. At 206, the PUSCH signal 202 is demodulated.

[0030] Figure 3 illustrates a generalized PUCCH receive chain. The PUCCH signal 302 is received at 304. At 304, channel estimation is performed on DM-RS symbols of the PUCCH. At 306, channel equalization is performed, and at 308, the PUCCH is demodulated. The PUSCH receive chain shown in the example of Figure 2 and the PUCCH receive chain shown in the example of Figure 3 are examples of receive chains that may not be able to decode PUSCH and PUCCH transmitted by a transmitter moving at a high speed rate.

[0031] Figure 4 shows a QPSK constellation diagram. The modulation technique used for digital communications limits the variation applied to the carrier as discrete information is transmitted. The original signal is divided into two independent components, I and Q. The data is divided into two channels (I and Q). Two bits are transmitted simultaneously (one bit per channel). The two carriers are transmitted together. The I and Q components are separated by a 90° angle and may be interpreted as orthogonal or perpendicular in phase. In pole representation, magnitude and phase are represented together, as exemplified in 402. Note that PUCCH modulation is generally QPSK.

[0032] QPSK modulation allows the carrier to vary in phase rather than frequency. The QPSK signal shifts between discrete phase states separated by 90°. For this reason, a QPSK symbol may be represented by four discrete values. As an example, the discrete values ​​"00", "01", "10", and "11" are shown in 402. In the QPSK modulation shown in 402, "11" may represent a 45° discrete value, "01" may represent a 135° discrete value, "00" may represent a 225° discrete value, and "10" may represent a 315° discrete value. Here, each discrete value has a carrier amplitude of 1.0.

[0033] The QPSK constellation diagram in 404 illustrates an equalized QPSK signal centered on each corresponding discrete value. This illustrates a QPSK constellation without significant Doppler shift.

[0034] A tilted QPSK constellation diagram is shown in 406. A tilted QPSK constellation diagram can be due to Doppler shift (the tilt increases as the Doppler shift increases). The Doppler shift manifests as a phase ramp across OFDM symbols. This can also be seen as an angular deviation of the complex symbols. OFDM symbols immediately adjacent to DM-RS may not show a large tilt, but symbols far from DM-RS may have a significant, uncompensable tilt. Therefore, signals transmitted from devices moving at high velocity rates may be difficult or impossible to decode by conventional network receivers due to the high phase deviation caused by the Doppler spread.

[0035] Figure 4 illustrates a QPSK constellation, but the aforementioned Doppler shift may be similar for QAM signals (e.g., 16-QAM modulated signals). In QAM modulation, discrete values ​​correspond to phase and amplitude states. The QAM constellation diagram may be the same as the QPSK constellation diagram with discrete values ​​at 45, 135, 225, and 315 degrees.

[0036] Figure 5 shows a 16-QAM constellation diagram. In a 16-QAM modulated signal, a continuous bitstream may be represented as a sequence, which can be divided into four groups in each of the four quadrants. In the 16-QAM constellation diagram 502, each quadrant can be interpreted as containing four groups. In 16-QAM, six bits are used to represent the phase and amplitude states. That is, four I and four Q values ​​are used to generate four bits for each symbol (2 4 = 16). Thus, the amplitude and phase of the radio signal may be restricted to one of 16 different discrete and measurable states, as shown in 502.

[0037] A tilted QAM constellation can be understood as being similar to the tilted QPSK plot shown in 406, which is due to Doppler shift (the tilt increases as the Doppler shift increases).

[0038] Furthermore, PUCCH does not use the DFT SC-FDMA precoding used in PUSCH data symbols. Also, as mentioned above, PUCCH modulation is generally QPSK. 4 QAM constellations are essentially the same as QPSK.

[0039] Figure 6 illustrates a PUCCH receiver processing chain according to several embodiments. The highlighted portion represents a novel processing that may be implemented to solve the problem of receiving PUCCH signals transmitted by a transmitter moving at a high rate of motion.

[0040] PUCCH channel estimation for DM-RS is performed in 602. DM-RS is the reference signal for PUCCH. PUCCH in format 1x and format 2x has multiple OFDM symbols that carry the pilot signal.

[0041] PUCCH format 1x typically has three DM-RS symbols located in the middle of the PUCCH slot. PUCCH format 2x typically has two DM-RS symbols, where the DM-RS symbols are typically located in the second and second-to-last symbols of the PUCCH slot. Thus, there is a difference in the processing of PUCCH format 1x and PUCCH format 2x. The following description is directed towards PUCCH format 1x.

[0042] For PUCCH format 1x, the phase difference between the first DM-RS and second DM-RS, the second DMRS and third DMRS, and the first DMRS and third DMRS OFDM symbols is calculated. In other words, the phase difference between all DMRS symbols is calculated. The first DM-RS and second DM-RS, the second DM-RS and third DM-RS, and the first DM-RS and third DM-RS OFDM symbols are correlated and the Doppler shift is determined. The Doppler shift is proportional to the phase difference across all DM-RS symbols in the channel. The Doppler shift is reported to L2 as a phase deviation in 606.

[0043] In step 608, phase correction is performed on the DM-RS and data symbols of PUCCH. That is, in step 608, the phase of the DM-RS and data symbols is compensated for by the estimated phase deviation performed in step 604. In step 610, PUCCH equalization is performed on the output of step 608.

[0044] PUCCH channel estimation is performed in 602 using DM-RS symbols. For PUCCH transmitted by transmitters moving at high velocity rates, a phase deviation resulting in a high Doppler shift is estimated in 604. The phase deviation estimated in 604 is reported to L2 in 606.

[0045] Figure 7 illustrates a PUSCH receiver processing chain according to several embodiments. The highlighted portion represents a novel processing that may be implemented to solve the problem of receiving PUSCH signals transmitted by a transmitter moving at a high rate of motion.

[0046] The received PUSCH is equalized, and an inverse discrete Fourier transform (IDFT) is performed at 702. At 704, Doppler shift information is received from Layer 2. The Doppler shift is proportional to the phase deviation. At 706, a first-level phase correction is performed. The first-level phase correction is performed on the IDFT output samples using the Doppler shift information received from L2. That is, the phase of the IDFT output samples may be corrected according to the Doppler shift information received from L2 at 704. Here, the Doppler shift appears as a phase spread across OFDM symbols.

[0047] The phase deviation on the output of the first-level phase correction 706 is measured at 708. The phase deviation may also be measured by moving all QAM symbols to the first quadrant by applying phase shifts of -π / 4, -π / 2, and -π / 3 radians to the symbols in the second, third, and fourth quadrants, respectively. Measuring the phase deviation may include calculating the difference between π / 4 radians or 45 degrees of the expected mean phase.

[0048] To obtain the accumulated phase correction, the phase deviation on the output of the first level of phase correction measured in 706 and the Doppler shift received from Layer 2 in 704 are accumulated in 710. The accumulated phase correction is reported to L2 in 712. This may be seen as a type of feedback in which the phase deviation measured in 708 is refined or improved. As a generalized example, suppose a Doppler shift corresponding to a value of 45° (or the equivalent value in radians) is taken in 704, and the phase deviation measurement result in 708 is determined to be another 5° of phase correction. In 710, 45° is accumulated with 5°, and 50° is reported to L2. The process in 706-710 may be repeated so that the phase deviation reported in 712 is refined in each iteration.

[0049] In 714, a second level of phase correction is performed on the output of 710. In 714, the phase is corrected based on the output of the first level of phase correction in 706 and the phase correction measured and accumulated in 708-710. In 716, the PUSCH is demodulated.

[0050] The Doppler shift information received from L2 at 704 may correspond to the phase deviation estimated and reported from PUCCH (see 604 and 608 in Figure 6). It is possible that PUCCH has not yet been received, or that the reported phase deviation from PUCCH is old, outdated, or invalid. In such cases, the Doppler shift information received from L2 at 704 may be reported as a value of zero (0).

[0051] If the Doppler shift received from L2 is zero, the processing at 714 may be performed twice.

[0052] The PUCCH processes in 604, 606, and 608, and the PUSCH processes in 704 and 706-714, provide a solution to the problem that conventional network receivers cannot decode PUCCH and / or PUSCH transmitted by transmitters moving at high speed rates. These processes determine the phase deviation caused by the high Doppler spread of high-speed transmitters and compensate for the phase deviation before demodulating the PUCCH and / or PUSCH.

[0053] Figure 8 is a flowchart illustrating an example of the process for receiving data transmitted from a high-speed mobile device.

[0054] As shown in Figure 8, process 800 may also include calculating the phase difference of the OFDM symbols of PUCCH from the OFDM symbols of PUCCH, which are received by the network receiver at 802 from the first DM-RS and second DM-RS, second DM-RS and third DM-RS, and first DM-RS and third DM-RS OFDM symbols of PUCCH. For example, the receiver may calculate the phase difference of the ODMA symbols of PUCCH from the first DM-RS and second DM-RS, second DM-RS and third DM-RS, and first DM-RS and third DM-RS OFDM symbols of PUCCH, as described above.

[0055] Process 800 may include, in 804, correlating the OFDM symbols of the first DM-RS and the second DM-RS, the second DM-RS and the third DM-RS, and the first DM-RS and the third DM-RS. For example, a receiver or device may correlate the OFDM symbols of the first DM-RS and the second DM-RS, the second DM-RS and the third DM-RS, and the first DM-RS and the third DM-RS as described above. Process 800 may include, in 806, determining a Doppler shift proportional to the phase difference across the DM-RS symbols in the channel. For example, a receiver or device may determine a Doppler shift proportional to the phase difference across the DM-RS symbols in the channel as described above. Process 800 may include, in 808, reporting the Doppler shift to Layer 2 (L2) of the protocol stack. For example, a receiver or device may report the Doppler shift to L2 of the protocol stack as described above. As further shown in Figure 8, process 800 may include compensating the channel estimation results and data symbols with a Doppler shift in 810. For example, the receiver or device may compensate the channel estimation results and data symbols with a Doppler shift as described above. Also, as shown in Figure 8, process 800 may include equalizing and demodulating the PUCCH in 812. For example, the receiver or device may equalize and demodulate the PUCCH as described above.

[0056] Figure 8 shows an example of blocks in process 800, but in some implementations, process 800 may include additional blocks, fewer blocks, different blocks, or blocks in different arrangements than those shown in Figure 8. In addition or alternatively, two or more blocks of process 800 may be executed in parallel.

[0057] Process 800 may include additional implementations, such as any single implementation or any combination of the implementations described below, and / or combinations with one or more other processes described elsewhere.

[0058] Figure 9 is a flowchart of an example of the process for receiving a PUSCH transmitted from a high-speed mobile device.

[0059] Process 900 may also include, in 902, performing a first-level phase correction on the received PUSCH by correcting the phase on the output sample of the IDFT from the Doppler shift received from L2. For example, the receiver of the device may perform a first-level phase correction on the received PUSCH by the receiver by correcting the phase on the output sample of the IDFT from the Doppler shift received from L2, as described above. Process 900 may also include, in 904, measuring the phase deviation on the output of the first-level phase correction, as shown in Figure 9. For example, the receiver of the device may measure the phase deviation on the output of the first-level phase correction, as described above. Further shown in Figure 9, process 900 may include, in 906, accumulating the measured phase deviation on the output of the first-level phase correction and the Doppler shift received from L2 to obtain an accumulated phase correction. Process 900 may also include, in 908, reporting the accumulated phase correction to L2. For example, the device's receiver may report the accumulated phase correction to L2, as described above.

[0060] Furthermore, as shown in Figure 9, process 900 may also include performing a second level of phase correction in 910 according to the measured phase deviation of the output of the first level of phase correction. For example, a receiver or device may perform a second level of phase correction in accordance with the measured phase deviation of the output of the first level of phase correction, as described above. Process 900 may also include demodulating PUSCH in 912. For example, a receiver or device may demodulate PUSCH, as described above.

[0061] Figure 9 shows an example of a block in process 900, but in some implementations, process 900 may include additional blocks, fewer blocks, different blocks, or blocks in different arrangements than those shown in Figure 9. In addition or alternatively, two or more blocks of process 900 may run in parallel.

[0062] Process 900 may include additional implementations, such as any single implementation or any combination of the implementations described below, and / or combinations with one or more other processes described elsewhere.

[0063] In the first implementation, measuring the phase deviation on the output of the first level of phase correction involves moving all quadrature amplitude modulation (QAM) symbols to the first quadrant by applying phase shifts of -π / 4, -π / 2, and -π / 3 radians to the symbols in the second, third, and fourth quadrants, respectively.

[0064] The second implementation may include, either alone or in combination with the first implementation, process 900 calculating the difference between the average phase of the QAM symbol and the expected average phase of π / 4 radians or 45 degrees.

[0065] In the third implementation, performing a first level of phase correction on PUSCH, either alone or in combination with the first and second implementations, includes receiving the Doppler shift reported to Layer 2 by Layer 1.

[0066] In the fourth implementation, if the Doppler shift value received from Layer 2 is zero, either alone or in combination with the first, second, and third implementations, the second level of phase correction is performed twice.

[0067] In the fifth implementation, the first, second, and third DM-RS symbols are consecutive DM-RS symbols, either on their own or in combination with one or more of the first to fourth implementations.

[0068] In the sixth implementation, the phase deviation is measured between all DM-RS symbols, either alone or in combination with one or more of the first through fifth implementations.

[0069] Other variations of the disclosed embodiments may also be understood and enabled by those skilled in the art when carrying out the features exemplified in the drawings, disclosures, and accompanying teachings of the claims.

[0070] In the claims, the term “comprising” does not exclude other elements or steps, nor does it exclude the indefinite article “a” or “an” from being plural.

[0071] A single processor, device, or other unit may implement the functionality of some of the items listed in the claims. The mere fact that certain means are listed in different dependent claims does not imply that combinations of these means cannot be used for merit.

[0072] Operations such as acquiring, accessing, analyzing, capturing, comparing, determining, inputting, obtaining, outputting, providing, storing or holding, performing calculations, simulating, receiving, warning, and stopping may be implemented as program code means and / or dedicated hardware of a computer program.

[0073] Computer programs may be stored and / or distributed on suitable media such as optical storage media or solid-state media, supplied together with or as part of other hardware, or in other forms such as via the Internet or other wired or wireless communication systems.

Claims

1. A method for decoding a physical uplink shared channel (PUSCH) and a physical uplink control channel (PUCCH) received by a receiver in a high-speed environment, With respect to the orthogonal frequency division multiplexing (OFDM) symbols of the first DM-RS, second DM-RS, and third DM-RS, which are consecutive demodulated reference signal (DM-RS) symbols of the PUCCH received by the receiver, The OFDM symbols of the first DM-RS and the OFDM symbols of the second DM-RS of the PUCCH, The OFDM symbols of the second DM-RS and the third DM-RS of the PUCCH, The OFDM symbols of the first DM-RS and the third DM-RS of the PUCCH, The phase difference of the OFDM symbol of PUCCH is calculated from the above, Correlating the OFDM symbols of the first DM-RS and the second DM-RS, the second DM-RS and the third DM-RS, and the first DM-RS and the third DM-RS, Based on the correlation between the first DM-RS and the second DM-RS, the correlation between the second DM-RS and the third DM-RS, and the correlation between the first DM-RS and the third DM-RS, a Doppler shift proportional to the phase difference across all the DM-RS symbols in the channel is determined. The aforementioned Doppler shift is reported to layer 2 of the protocol stack, Compensating the channel estimation results and data symbols with the Doppler shift, Equalizing and demodulating the aforementioned PUCCH, The first level of phase correction is performed on the PUSCH received by the receiver by correcting the phase on the output samples of the inverse discrete Fourier transform (IDFT) from the Doppler shift received from layer 2, Measuring the phase deviation on the output of the first level phase correction, To obtain the accumulated phase correction, the phase deviation on the measured output of the first level phase correction and the Doppler shift received from layer 2 are accumulated, The accumulated phase correction is reported to Layer 2, Performing a second level of phase correction according to the measured phase deviation of the output of the first level of phase correction, To demodulate the aforementioned PUSCH, A method for providing this.

2. The method according to claim 1, wherein measuring the phase deviation on the output of the first level of phase correction includes moving all quadrature amplitude modulation (QAM) symbols to the first quadrant by applying phase shifts of -π / 2, -π, and -3 / 2π radians to the symbols in the second, third, and fourth quadrants, respectively.

3. The method according to claim 2, further comprising calculating the difference between the mean phase of the QAM symbol and the expected mean phase of π / 4 radians or 45 degrees.

4. The method according to claim 1, wherein performing the first level of phase correction on the PUSCH includes receiving the Doppler shift reported to Layer 2 by Layer 1.

5. The method according to claim 4, further comprising performing the second level phase correction twice if the value of the Doppler shift received from layer 2 is zero.

6. The method according to claim 1, wherein the phase deviation is measured between all of the DM-RS symbols.

7. A device for decoding physical uplink shared channels (PUSCH) and physical uplink controlled channels (PUCCH) received by a receiver in a high-speed environment, Memory configured to store multiple instructions, With respect to the orthogonal frequency division multiplexing (OFDM) symbols of the first DM-RS, second DM-RS, and third DM-RS, which are consecutive demodulated reference signal (DM-RS) symbols of the PUCCH received by the receiver, The OFDM symbols of the first DM-RS and the OFDM symbols of the second DM-RS of the PUCCH, The OFDM symbols of the second DM-RS and the third DM-RS of the PUCCH, The OFDM symbols of the first DM-RS and the third DM-RS of the PUCCH, The phase difference of the OFDM symbol of PUCCH is calculated from the above, Correlating the OFDM symbols of the first DM-RS and the second DM-RS, the second DM-RS and the third DM-RS, and the first DM-RS and the third DM-RS, Based on the correlation between the first DM-RS and the second DM-RS, the correlation between the second DM-RS and the third DM-RS, and the correlation between the first DM-RS and the third DM-RS, a Doppler shift proportional to the phase difference across all the DM-RS symbols in the channel is determined. The aforementioned Doppler shift is reported to layer 2 of the protocol stack, Compensating the channel estimation results and data symbols with the Doppler shift, Equalizing and demodulating the aforementioned PUCCH, The first level of phase correction is performed on the PUSCH received by the receiver by correcting the phase on the output samples of the inverse discrete Fourier transform (IDFT) from the Doppler shift received from layer 2, Measuring the phase deviation on the output of the first level phase correction, To obtain the accumulated phase correction, the phase deviation on the measured output of the first level phase correction and the Doppler shift received from layer 2 are accumulated, The accumulated phase correction is reported to Layer 2, Performing a second level of phase correction according to the measured phase deviation of the output of the first level of phase correction, To demodulate the aforementioned PUSCH, To perform the above, a processor circuit configured to execute the plurality of instructions and coupled to the memory, A device equipped with the following features.

8. The apparatus according to claim 7, wherein measuring the phase deviation on the output of the first level of phase correction includes moving all quadrature amplitude modulation (QAM) symbols to the first quadrant by applying phase shifts of -π / 2, -π, and -3 / 2π radians to the symbols in the second, third, and fourth quadrants, respectively.

9. The apparatus according to claim 8, wherein the processor circuit is further configured to execute the plurality of instructions in order to perform the calculation of the difference between the average phase of the QAM symbol and the expected average phase of π / 4 radians or 45 degrees.

10. The apparatus according to claim 7, wherein performing the first level of phase correction on the PUSCH includes receiving the Doppler shift reported to Layer 2 by Layer 1.

11. The apparatus according to claim 10, wherein if the value of the Doppler shift received from layer 2 is zero, the second level phase correction is performed twice.

12. The apparatus according to claim 7, wherein the phase deviation is measured between all of the DM-RS symbols.

13. A mobile device configured to transmit physical uplink shared channels (PUSCH) and physical uplink control channels (PUCCH) in a high-speed environment, Regarding the quadrature frequency division multiplexing (OFDM) symbols of the first DM-RS, second DM-RS, and third DM-RS, which are consecutive demodulated reference signal (DM-RS) symbols received by the receiver from the mobile device, The OFDM symbols of the first DM-RS and the OFDM symbols of the second DM-RS of the PUCCH, The OFDM symbols of the second DM-RS and the third DM-RS of the PUCCH, The OFDM symbols of the first DM-RS and the third DM-RS of the PUCCH, The phase difference of the OFDM symbol of PUCCH is calculated from the above, Correlating the OFDM symbols of the first DM-RS and the second DM-RS, the second DM-RS and the third DM-RS, and the first DM-RS and the third DM-RS, Based on the correlation between the first DM-RS and the second DM-RS, the correlation between the second DM-RS and the third DM-RS, and the correlation between the first DM-RS and the third DM-RS, a Doppler shift proportional to the phase difference across all the DM-RS symbols in the channel is determined. The aforementioned Doppler shift is reported to layer 2 of the protocol stack, Compensating the channel estimation results and data symbols with the Doppler shift, Equalizing and demodulating the aforementioned PUCCH, The first level of phase correction is performed on the PUSCH received by the receiver by correcting the phase on the output samples of the inverse discrete Fourier transform (IDFT) from the Doppler shift received from layer 2, Measuring the phase deviation on the output of the first level phase correction, To obtain the accumulated phase correction, the phase deviation on the measured output of the first level phase correction and the Doppler shift received from layer 2 are accumulated, The accumulated phase correction is reported to Layer 2, Performing a second level of phase correction according to the measured phase deviation of the output of the first level of phase correction, To demodulate the aforementioned PUSCH, eNodeB configured to perform the following: A communication system equipped with [the following features].

Images