Method and transmitter for transmitting data in a wireless communication system

Abstract

The present application provides a method and a transmitter for sending data in a wireless communication system. The time-frequency resources of a specific parameter set can be used to send OFDM symbols, and the cyclic prefix of the OFDM symbol is longer than the cyclic prefix of other OFDM symbols. This may complicate the alignment of different parameter sets. Disclosed herein is a time-frequency resource partitioning that can assist in symbol alignment and / or subframe alignment of different parameter sets.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 371,104, filed on August 4, 2016, entitled “Symbol and Subframe Alignment in a Frame Structure for a Wireless Communication System,” and claims priority to U.S. Provisional Patent Application No. 62 / 382,658, filed on September 1, 2016, entitled “Symbol Boundary Alignment for Different Reference Parameter Sets,” both of which are incorporated herein by reference in their entirety. Technical Field

[0003] The present application relates to wireless communications, and more particularly, to symbol and / or subframe alignment of different parameter sets in a wireless communication system. Background Art

[0004] In some wireless communication systems, user equipment (UE) communicates wirelessly with one or more base stations. Wireless communication from the UE to the base station is called uplink communication. Wireless communication from the base station to the UE is called downlink communication. Resources are required to perform uplink and downlink communications. For example, in downlink communication, the base station can wirelessly send data to the UE at a specific frequency and for a specific duration. The frequency and duration are examples of resources.

[0005] Time-frequency resources are allocated for communication between UEs and base stations. Multiple access occurs when more than one UE is scheduled on a set of time-frequency resources. In the case of downlink communication, each UE uses a portion of the time-frequency resources to receive base station data from the base station, or in the case of uplink communication, each UE uses a portion of the time-frequency resources to send data to the base station.

[0006] Wireless communication between a base station and a UE may be performed by transmitting orthogonal frequency-division multiplexing (OFDM) symbols. The frequency spacing used between subcarriers of an OFDM symbol is called a subcarrier spacing.

[0007] It may be desirable to have a certain degree of alignment between OFDM symbols having different subcarrier spacings. Summary of the invention

[0008] A carrier that transmits a signal of OFDM symbols has a "parameter set". A parameter set for a carrier refers to a subset of physical layer parameters used to transmit the signal. The parameter set may include a combination or subset of the following: a transmission time unit (TTU) or transmission time interval (TTI) used to transmit the signal on the carrier, an OFDM symbol duration of an OFDM symbol transmitted on the carrier, a cyclic prefix (CP) length for each OFDM symbol transmitted on the carrier, and a subcarrier spacing between subcarrier frequencies on which the signal is transmitted. Thus, a specific subcarrier spacing may correspond to a specific parameter set.

[0009] Different parameter sets can coexist. For example, a base station can adopt the following two parameter sets: in a first frequency subband, the base station can send and receive OFDM symbols with a subcarrier spacing of 15 kHz, and in a second frequency subband, the base station can send and receive OFDM symbols with a subcarrier spacing of 30 kHz.

[0010] It may be desirable to have a certain degree of alignment across different parameter sets. However, the time-frequency resources of a particular parameter set may be used to transmit OFDM symbols with two or more different cyclic prefix lengths. This may complicate the alignment of different parameter sets.

[0011] Disclosed herein is a time-frequency resource partitioning that can assist with symbol alignment and / or subframe alignment for different parameter sets. In some embodiments, a long cyclic prefix or an additional portion of a long cyclic prefix is ​​used as part of a guard period between downlink and uplink OFDM symbols.

[0012] In one embodiment, a method for sending data in a wireless communication system is provided. The method includes sending k consecutive OFDM symbols with a first subcarrier spacing. The first OFDM symbol of the k consecutive OFDM symbols has a duration t1, and the remaining OFDM symbols of the k consecutive OFDM symbols have a duration t2<t1. The total duration of the k consecutive OFDM symbols is T ms. The method also includes sending n>k consecutive OFDM symbols with a second subcarrier spacing, and the second subcarrier spacing is greater than the first subcarrier spacing. The first OFDM symbol of the n consecutive OFDM symbols has a duration t3, and the remaining OFDM symbols of the n consecutive OFDM symbols have a duration t4<t3. The total duration of the n consecutive OFDM symbols is T ms. In one embodiment, T=0.5ms. In another embodiment, T=0.25ms.

[0013] In another embodiment, a method for transmitting data in a wireless communication system is provided. The method includes transmitting data in a 15kHz×2 n k consecutive OFDM symbols are sent on a group of subcarriers with a subcarrier spacing of , where n is an integer and n≥1. The first OFDM symbol of the k consecutive OFDM symbols has a duration t1, and the remaining OFDM symbols of the k consecutive OFDM symbols have a duration t2<t1. The total duration of the k consecutive OFDM symbols is Tms. In one embodiment, T=0.5ms. In another embodiment, T=0.25ms.

[0014] In another embodiment, a method for transmitting data in a wireless communication system is provided. The method includes transmitting a plurality of OFDM symbols according to a frame structure. The frame structure includes k>1 consecutive OFDM symbol durations, followed by j>1 consecutive OFDM symbol durations. The k consecutive OFDM symbol durations and the j consecutive OFDM symbol durations are within the same subframe. Each of the k consecutive OFDM symbol durations has a duration t1 and a first cyclic prefix (CP) length. Each of the j consecutive OFDM symbol durations has a duration t2>t1 and a second CP length greater than the first CP length.

[0015] Optionally, in any of the aforementioned embodiments, the n consecutive OFDM symbols and the k consecutive OFDM symbols are sent simultaneously.

[0016] Optionally, in any one of the aforementioned embodiments, the k consecutive OFDM symbols are sent on a first subcarrier set with the first subcarrier spacing, and the n consecutive OFDM symbols are sent on a second subcarrier set with the second subcarrier spacing.

[0017] Optionally, in any one of the aforementioned embodiments, the first subcarrier set and the second subcarrier set belong to different carriers.

[0018] Optionally, in any one of the aforementioned embodiments, the first subcarrier set and the second subcarrier set belong to the same carrier.

[0019] Optionally, in any one of the aforementioned embodiments, the first subcarrier spacing is 15 kHz and the second subcarrier spacing is 30 kHz.

[0020] Optionally, in any one of the aforementioned embodiments, the first subcarrier spacing is 30 kHz and the second subcarrier spacing is 60 kHz.

[0021] Optionally, in any of the aforementioned embodiments, k=7 and n=14.

[0022] Optionally, in any one of the aforementioned embodiments: the first OFDM symbol of the k consecutive OFDM symbols has a cyclic prefix, which is longer than the cyclic prefix of each of the remaining OFDM symbols of the k consecutive OFDM symbols; and the first OFDM symbol of the n consecutive OFDM symbols has a cyclic prefix, which is longer than the cyclic prefix of each of the remaining OFDM symbols of the n consecutive OFDM symbols.

[0023] Optionally, in any one of the aforementioned embodiments, a rear edge of the first OFDM symbol of the k consecutive OFDM symbols is aligned with a rear edge of the second OFDM symbol of the n consecutive OFDM symbols.

[0024] Optionally, in any of the aforementioned embodiments, the second subcarrier spacing is an integer multiple of the first subcarrier spacing.

[0025] Optionally, in any of the aforementioned embodiments, the integer multiple is a power of two.

[0026] Optionally, in any of the foregoing embodiments, the first subcarrier spacing is 15kHz×2 i , wherein i is an integer and i ≥ 0, and wherein the second subcarrier spacing is 15 kHz × 2 j , where j is an integer and j>i.

[0027] Optionally, in any of the aforementioned embodiments, the method is executed by a base station.

[0028] Disclosed are corresponding base stations, UEs and transmitters, which are used to perform the methods described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Embodiments will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0030] Figure 1 is a block diagram of a wireless communication system according to one embodiment;

[0031] Figure 2 and Figure 3 Two exemplary relationships between a subframe, a transmission time unit (TTU) and a scheduling interval are shown respectively;

[0032] Figure 4 shows a time slot in a long term evolution (LTE) system;

[0033] Figure 5 A table showing parameters for different parameter sets is shown;

[0034] Figures 6 to 14 Examples of time-frequency resources with different parameter sets for subframe alignment are shown;

[0035] Figures 15 to 31 Examples of time-frequency resources with different parameter sets for symbol alignment are shown;

[0036] Fig.32 is a flow chart of an embodiment of a method for transmitting data, which method may be performed by a transmitter;

[0037] Figure 33 to Figure 37 Other examples of time-frequency resources with different parameter sets are shown;

[0038] Fig.38 Two groups of time-frequency resources are shown with symbols aligned, but the first OFDM symbols of two different subframes are not aligned;

[0039] Fig.39 is a block diagram of an embodiment processing system;

[0040] Fig.40 is a block diagram of a transceiver suitable for sending and receiving signaling over a telecommunications network; and

[0041] Figure 41 to Figure 43 is an exemplary sending method. DETAILED DESCRIPTION

[0042] For illustrative purposes, certain exemplary embodiments will now be explained in more detail hereinafter in conjunction with the accompanying drawings.

[0043] Figure 1 is a block diagram of a wireless communication system according to one embodiment. The wireless communication system includes a base station 104 that communicates with UEs 106a-c.

[0044] The base station 104 may be part of an access network (not shown). The term "base station" includes any device that wirelessly communicates with a UE. Therefore, in some implementations, the base station 104 may be referred to by other names, such as a transmit and receive point (TRP), a base transceiver station, a wireless base station, a network node, a transmit / receive node, a node B, an evolved node B (eNB), a gNB sometimes referred to as a "gigabit" node B, a relay station, or a remote radio head. In addition, in some embodiments, the functionality of the base station 104 may be distributed. For example, some components of the base station 104 may be remote from the device housing the antenna of the base station 104 and may be coupled to the device housing the antenna via a communication link (not shown).

[0045] Figure 1 An example of a base station 104 is shown in more detail in . The base station 104 includes a scheduler 110 and a transmitter 112. The transmitter 112 implements at least part of the downlink physical layer. The transmitter 112 includes a serial-to-parallel converter 114, an inverse fast Fourier transform (IFFT) block 116 that implements an IFFT algorithm, and a parallel-to-serial converter 118. The base station 104 also includes at least one antenna 120 for sending and receiving OFDM symbols. Only one antenna is shown. The transmitter 112 may also include other components, such as a forward error correction (FEC) encoder, but these other components are omitted for clarity. The base station 104 also includes other components, such as a receiver 113 for receiving uplink messages from a UE, but the details of the other components are omitted for clarity.

[0046] The scheduler 110 and the IFFT block 116 and other components of the transmitter 112 may be implemented by a processor that executes instructions that cause the processor to perform the operations of the scheduler 110 and the IFFT block 116 and other components of the transmitter 112. Different processors or the same processor may be used to implement each of the scheduler 110 and the IFFT block 116 and other components of the transmitter 112. Alternatively, the scheduler 110 and / or the IFFT block 116 and / or other components of the transmitter 112 may be implemented using an application specific integrated circuit, such as an application specific integrated circuit (ASIC), a graphics processing unit (GPU), or a programmed field programmable gate array (FPGA) for performing the functions of the scheduler 110 and / or the IFFT block 116 and / or other components of the transmitter 112.

[0047] Figure 11. The UE 106a is shown in more detail in FIG. 1. The UE 106a includes a transmitter 122. The transmitter 122 implements at least part of the downlink physical layer. The transmitter 122 includes a serial to parallel converter 124, an IFFT block 126 for implementing an IFFT algorithm, and a parallel to serial converter 128. The UE 106a also includes at least one antenna 130 for sending / receiving OFDM symbols. Only one antenna is shown. The transmitter 122 may also include other components, such as an FEC encoder, but these other components are omitted for clarity. The UE 106a also includes other components, such as a receiver 133 for receiving downlink messages from the base station 100, but the details of the other components are omitted for clarity.

[0048] The IFFT block 126 and other components of the transmitter 122 may be implemented by a processor that executes instructions that cause the processor to perform the operations of the IFFT block 126 and other components of the transmitter 122. Alternatively, the IFFT block 126 and / or other components of the transmitter 122 may be implemented using an application specific integrated circuit, such as an ASIC, GPU, or FPGA for performing the functions of the IFFT block 126 and / or other components of the transmitter 122.

[0049] In operation, the coded bits 142 at the base station 104 are transmitted to the UE served by the base station 104 via one or more OFDM symbols. The serial-to-parallel converter 114 is used to make the blocks of coded bits 142 in serial form appear as parallel inputs to the IFFT block. The IFFT block 116 implements an inverse discrete Fourier transform operation to obtain a plurality of OFDM symbol samples. A cyclic prefix (CP) is added to the beginning of the OFDM symbol samples by repeating the last m symbols at the beginning of the OFDM symbol samples. The CP can assist in mitigating inter-symbol interference and / or can enable the application of cyclic convolution signal processing techniques. The CP duration can be between 1 / 4 and 1 / 32 of the useful symbol duration and can be set according to the length of the multipath channel.

[0050] After the CP is added to the beginning of the OFDM symbol samples, the CP and symbol samples may be converted to serial form using a parallel-to-serial converter 118 to obtain a duration of t s OFDM symbol 144 is sent using a portion of a set of time-frequency resources 146 .

[0051] OFDM symbol 144 is only one symbol in time-frequency resource set 146. Time-frequency resource set 146 includes a series of OFDM symbols one after another. In addition, time-frequency resource set 146 is divided into three subbands: one subband 143, in which the subcarrier spacing of OFDM symbols is 15kHz, another subband 145, in which the subcarrier spacing of OFDM symbols is 30kHz, and another subband 147, in which the subcarrier spacing of OFDM symbols is 60kHz. The subcarrier spacing of OFDM symbol 144 is 30kHz, which falls within subband 145.

[0052] Note that not all frequencies in OFDM symbol 144 must be used to transmit data to UE 106a. Instead, some frequencies in OFDM symbol 144 may be used to transmit data to other UEs served by base station 106. For example, block 148 shown in hatching represents a resource block allocated to UE 106a. Resource block 148 includes f A to f B Frequency set. Within a specific duration, the f of several OFDM symbols is A to f B The frequency set is assigned to the UE 106a. In some embodiments, the duration may be equal to a transmission time unit (TTU), a subframe, and / or a scheduling interval.

[0053] The scheduler 110 determines which resources in the time-frequency resource set 146 are to be allocated to the UE 106a. The scheduler 110 uses a scheduling algorithm to decide which resources are allocated to which UE. An example of a scheduling algorithm that can be used by the scheduler 110 is a proportionally fair (PF) scheduling algorithm. The scheduler 110 can grant resource partitions of different sizes to different UEs.

[0054] The operation of UE 106a in the uplink is similar to the base station downlink. The uplink resource partition is used by UE 106a to send coded bits 156 via OFDM symbols. The serial form of the coded bits 156 is grouped using a serial-to-parallel converter 124 to present a parallel input to the IFFT block 126. The IFFT block 126 implements an inverse discrete Fourier transform operation to obtain multiple OFDM symbol samples.

[0055] UE 106b and UE 106c may communicate with base station 104 using a different set of parameters than UE 106a. As an example, UE 106b may communicate with base station 104 via subband 143 using OFDM symbols with a subcarrier spacing of 15 kHz. As another example, UE 106c may communicate with base station 104 via subband 147 using OFDM symbols with a subcarrier spacing of 60 kHz.

[0056] Notice, Figure 1 This is just one example. In another example, base station 104 may actually be multiple base stations that collaborate to serve the UE, and scheduler 110 may be located within the controller. In yet another example, there may be separate base stations that send and receive communications, each using a different set of parameters. In addition, although Figure 1 Three subbands are shown in FIG, but there may be more or fewer subbands. Figure 1 The parameter sets shown in are different parameter sets.

[0057] The time-frequency resource sets may be divided into different time intervals, such as subframes, transmission time units (TTUs), scheduling intervals, etc. Depending on the embodiment, a subframe may have multiple TTUs or exactly one TTU. In some embodiments, a TTU may even be longer than a subframe. A TTU is sometimes referred to as a transmission time interval (TTI). A scheduling interval typically includes at least one TTU, and depending on the embodiment, a scheduling interval may have a duration equal to, longer than, or shorter than a subframe. Figure 2 and Figure 3 Two exemplary relationships between subframes, TTUs, and scheduling intervals are shown. "DL" refers to one or more downlink OFDM symbols with a specific subcarrier spacing, "UL" refers to one or more uplink OFDM symbols with the same subcarrier spacing, and "GP" refers to the guard period between uplink and downlink. Figure 2 In , a subframe is longer than a single TTU and the scheduling interval is equal to the subframe duration. Figure 3 In , the scheduling interval is equal to two subframes, and the TTU is longer than a single subframe. Figure 2 and Figure 3 In, the scheduling interval includes TTU. Figure 2 and Figure 3 Just an example.

[0058] In the following embodiments, the term subframe will be used. For example, the concept of subframe alignment will be discussed below. However, depending on the embodiment, subframe alignment may also be referred to by other names, such as TTU alignment or scheduling interval alignment. For example, if a subframe happens to have the same duration as a TTU, then interchangeably, subframe alignment may be referred to as TTU alignment.

[0059] A subframe in a long term evolution (LTE) system has a specific definition: 1 ms consisting of two 0.5 ms time slots. Figure 4A time slot in an LTE system is shown. The time slot has a duration of seven OFDM symbols. In an LTE system, the CP of the first OFDM symbol of each time slot is approximately 0.52 μs, which is longer than the CP of each of the subsequent six OFDM symbols in the time slot. The OFDM symbols with longer CP are shown using hatching along the top of the OFDM symbols, as shown at 166.

[0060] Regardless of the subcarrier frequency spacing, when a particular time interval includes an OFDM symbol with a longer CP than the CP of other OFDM symbols, the OFDM symbol with the longer CP will be referred to as a "long CP OFDM symbol". All other OFDM symbols in the time interval will be referred to as "normal CP OFDM symbols". Figure 4 In the time interval including one LTE slot, there is one long CP OFDM symbol indicated by hatching 166, followed by six normal CP OFDM symbols.

[0061] exist Figure 4 In the example above, the sum of the duration of each OFDM symbol in each slot (6×71.36μs+71.88μs) is equal to 0.5ms. Note that the duration of each OFDM symbol has been rounded, which is why 6×71.36μs+71.88μs is not exactly equal to 0.5ms. In implementation, these durations are such that the sum of the durations is equal to 0.5ms.

[0062] The length of the OFDM symbol, that is, the OFDM symbol duration t s Related to the subcarrier spacing. The closer the subcarrier spacing, the longer the OFDM symbol duration t s The longer. Figure 5 A table is shown showing the OFDM symbol duration t for the following subcarrier spacings: 7.5kHz, 15kHz, 30kHz, 60kHz, 120kHz, 240kHz and 480kHz s , CP length, the excess of the long CP relative to the regular CP, the number of symbols per subframe, the subframe length, and the CP overhead. Some numbers in the table are rounded. Different carrier spacings correspond to different parameter sets. The row indicating the CP length gives the long CP length and the regular CP length for each subcarrier spacing. For example, for a 30kHz subcarrier spacing, the long CP OFDM symbol is 0.26μs longer than the regular CP OFDM symbol. This can be obtained from Figure 5 As can be seen, the parameter set is scalable in terms of subcarrier spacing, OFDM symbol duration, and CP length. For example, a 15 kHz subframe can fit into four 60 kHz subframes.

[0063] exist Figure 5 In the exemplary table in , a subframe is defined as seven OFDM symbols regardless of the parameter set. This is just an example. The number of symbols in a subframe may be different for different parameter sets. In addition, in some embodiments, for some or all parameter sets, the length of a subframe or TTU or scheduling interval may change dynamically or semi-dynamically over time.

[0064] Back to Figure 1 , base station 104 uses three different parameter sets: 15kHz subcarrier spacing, 30kHz subcarrier spacing, and 60kHz subcarrier spacing. It may be desirable to have alignment between different coexistence parameter sets. The alignment may be subframe alignment or symbol alignment. The presence of long CP OFDM symbols may complicate the alignment of different parameter sets. LTE has long CP OFDM symbols at the beginning of each time slot, such as Figure 4 If a non-LTE subframe with a subcarrier spacing of 15 kHz includes a long CP symbol to align with an LTE subframe, a different parameter set may also use scaled long CP OFDM symbols to be compatible with an LTE subframe, or to be compatible with a non-LTE subframe with a subcarrier spacing of 15 kHz.

[0065] In the embodiments below, a time-frequency allocation structure for different parameter sets that allows alignment of different parameter sets is disclosed. Specifically, some of the embodiments below are in the context of a time division duplex (TDD) system. In a TDD system, uplink and downlink communications share the same frequency band. Therefore, in a TDD system, communications alternate over time between uplink and downlink, with a guard period (GP) being used to provide a temporal interval between uplink and downlink communications. "Guard period" is used herein to indicate a duration during which there is no typical uplink or downlink transmission. Alternatively, the guard period is sometimes referred to as a blank period.

[0066] However, even if the exemplary embodiments below are in the context of a TDD system, in a unified duplex frame structure, the alignment scheme shown herein may also include a frequency division duplex (FDD) frame structure. In an FDD system, there are usually different interference problems between the uplink and downlink because the uplink and downlink transmissions do not share the same frequency band. However, there may be future applications in which a unified frame structure is used for TDD and FDD. When a unified frame structure is used and the system switches from FDD to TDD, the system can continue to use the same frame structure. Using a unified frame structure can avoid the system having to ensure that the frame structure is aligned whenever switching from FDD to TDD.

[0067] Subframe Alignment

[0068] Subframe alignment occurs when there is boundary alignment between groups of OFDM symbols of different parameter sets. There may not be symbol-by-symbol alignment of different parameter sets, but the start of a group of OFDM symbols in one parameter set is aligned with the start of another group of OFDM symbols in another parameter set. An exemplary embodiment with subframe alignment is described below. Symbol alignment is discussed later.

[0069] Figure 6 1 ms time intervals of time-frequency resources with different parameter sets are shown. A time-frequency resource with a subcarrier spacing of 15 kHz is shown at 202, and a time-frequency resource with a subcarrier spacing of 30 kHz is shown at 204. Long CP OFDM symbols are again shown using hatching along the top of the OFDM symbol. Blocks marked with "D" or unmarked are downlink OFDM symbols, and blocks marked with "U" are uplink OFDM symbols. Blocks marked with "GP" are symbols used as guard periods, during which no data is transmitted. This will also be used in subsequent figures Figure 6 The symbols in .

[0070] A guard period is inserted whenever there is a transition from uplink to downlink, and vice versa. In this embodiment, the 15kHz parameter set has one subframe every 1ms and the 30kHz parameter set has one subframe every 0.5ms. The OFDM symbol of the 30kHz parameter set is scaled to half the length of the OFDM symbol of the 15kHz parameter set. Therefore, each subframe of the 15kHz parameter set is aligned in time with the start of the subframe of the 30kHz parameter set. As shown at 208 and 210, the guard period and uplink OFDM symbols of the 15kHz parameter set and the 30kHz parameter set are also symbol aligned. The guard period and uplink symbols are symbol aligned because they appear later in time than the last long OFDM symbol 217 of the 30kHz parameter set within the subframe of the 15kHz parameter set, so the guard period and uplink symbols are not affected by symbol misalignment. In the illustrated embodiment, the guard period and uplink symbols are located at the end of the subframe of the 15kHz parameter set.

[0071] The subframe of the 15kHz parameter set shown at 202 is a "downlink dominated" subframe because it primarily includes downlink OFDM symbols. Similarly, the second subframe of the 30kHz parameter set shown at 204 is downlink dominated. As shown at 214, a 15kHz parameter set time-frequency allocation structure with the following repeating pattern can be used: a first 15kHz downlink dominated subframe, followed by a second 15kHz downlink dominated subframe, followed by a 15kHz uplink subframe. As shown at 215, the corresponding 30kHz parameter set time-frequency allocation structure can be the following repeating pattern: a 30kHz downlink subframe, followed by a 30kHz downlink dominated subframe, followed by a 30kHz downlink subframe, followed by a 30kHz downlink dominated subframe, followed by two 30kHz uplink subframes.

[0072] exist Figure 6 In a TDD time interval, there may be a downlink OFDM symbol and an uplink OFDM symbol. The time interval between which the downlink OFDM symbol and the uplink OFDM symbol exist is called a "self-contained TDD time interval". Figure 6 The time-frequency allocation structure in can be viewed as a self-contained TDD time interval of 1 ms.

[0073] Note that, depending on the parameter set, Figure 6 The amount of OFDM symbol duration used as a guard period in the OFDM symbol 216 may vary. For example, in an alternative embodiment, the first portion of the guard period 216 in the interval 204, which is equal in duration to a conventional CP OFDM symbol, may instead be used to transmit data via a conventional CP OFDM symbol. As another example, the OFDM symbol 218 may instead be used as a portion of the guard period such that the guard period in the 30 kHz parameter set is equal to the duration of three conventional CP OFDM symbols.

[0074] Figure 7 0.5 ms time intervals of time-frequency resources with different parameter sets are shown. At 252, a time-frequency resource with a subcarrier spacing of 15 kHz is shown, at 254, a time-frequency resource with a subcarrier spacing of 30 kHz is shown, and at 256, a time-frequency resource with a subcarrier spacing of 60 kHz is shown. Figure 7Represents a time-frequency allocation structure with a self-contained TDD time interval of 0.5ms. The uplink OFDM symbols are symbol-aligned because they appear later in time than the last long OFDM symbol of the 60kHz parameter set part within the 0.5ms time interval of the 15kHz parameter set shown, so the uplink symbols are not affected by symbol misalignment. In the illustrated embodiment, the uplink symbol is located at the end of the 0.5ms time interval. Specifically, the last 71.36μs of 0.5ms is used for the uplink. This means that there is one uplink OFDM symbol for the 15kHz parameter set in the 0.5ms interval, two uplink OFDM symbols for the 30kHz parameter set in the 0.5ms interval, and four uplink OFDM symbols for the 60kHz parameter set in the 0.5ms interval. The guard period is configurable. Examples of possible guard periods are shown at 258, 260 and 262. It is worth noting that the guard period of the 30kHz parameter set and / or the 60kHz parameter set can be set smaller or larger.

[0075] Figure 8 0.5 ms time intervals of time-frequency resources with different parameter sets are shown. At 282, a time-frequency resource with a subcarrier spacing of 15 kHz is shown, and at 284, a time-frequency resource with a subcarrier spacing of 60 kHz is shown. Figure 8 In the example, the 60kHz parameter set has a self-contained TDD time interval of 14 OFDM symbols. In this example, the subframe for the 60kHz parameter set is 7 OFDM symbols (0.125ms), and the last two OFDM symbols of every other subframe of the 60kHz parameter set are uplink OFDM symbols. The remaining symbols are used for downlink OFDM symbols and protection periods. The subframe for the 15kHz parameter set is 0.5ms, and the subframes shown for the 15kHz parameter set are only used for downlink transmission. Whenever an OFDM symbol of the 15kHz parameter set overlaps in time with an uplink OFDM symbol in the 60kHz parameter set, the overlapping OFDM symbol of the 15kHz parameter set is set as a protection period instead to reduce interference with uplink transmissions in the 60kHz parameter set. Only four of the seven possible OFDM symbols in the 15kHz subframe shown are used for data transmission. Note, however, that due to symbol misalignment, the third OFDM symbol 285 in the 15 kHz subframe has only a small overlap 286 with the uplink OFDM symbol in the 60 kHz subframe. Therefore, in an alternative embodiment, the third OFDM symbol 285 in the 15 kHz subframe may be used to transmit data with the understanding that there may be some interference with uplink transmissions in the 60 kHz subframe.

[0076] exist Figure 8In a variation of the embodiment in, at the end of every other subframe of the 60kHz parameter set, there may be only one uplink OFDM symbol instead of two uplink OFDM symbols. In every other subframe of the 60kHz parameter set, before two or three uplink OFDM symbols, there may also be or may alternatively be a guard period with a duration equal to one normal CP OFDM symbol instead of two normal CP OFDM symbols.

[0077] Fig. 9 Shows Figure 8 A variation of , in which, in the second shown subframe of the 60kHz parameter set, there is one uplink OFDM symbol, and the guard period preceding the uplink OFDM symbol is equal in duration to one normal CP OFDM symbol. In the fourth shown subframe of the 60kHz parameter set, there are still two uplink OFDM symbols, but the guard period preceding the two uplink OFDM symbols is equal in duration to only one normal CP OFDM symbol. Fig. 9 In the embodiment of the present invention, five of the possible seven OFDM symbols in the illustrated subframe of the 15kHz parameter set can be used for downlink transmission. The remaining two OFDM symbols in the illustrated subframe of the 15kHz parameter set are set as guard periods to mitigate interference with uplink transmission in the 60kHz parameter set.

[0078] Fig.10 Shows Figure 8 A variant of , wherein in every other subframe of the 60kHz parameter set, there is an uplink OFDM symbol preceded by a guard period equal to one OFDM symbol in duration. In this embodiment, five of the possible seven OFDM symbols in the illustrated subframe of the 15kHz parameter set may be used for downlink transmission. The remaining two OFDM symbols in the illustrated subframe of the 15kHz parameter set are set as guard periods to mitigate interference with uplink transmissions in the 60kHz parameter set.

[0079] Fig.11A variant is shown in which the 60kHz parameter set has a self-contained TDD time interval of 7 OFDM symbols (0.125ms). Before each long CP OFDM symbol of the 60kHz parameter set, there is an uplink regular CP OFDM symbol, and the guard period before the uplink regular CP OFDM symbol is equal to the duration of one regular CP OFDM symbol. This embodiment has a possible drawback in which five of the seven available OFDM symbols in the shown subframe of the 15kHz parameter set are set as guard periods to mitigate interference with uplink transmissions in the 60kHz parameter set. The fifth OFDM symbol in the shown subframe of the 15kHz parameter set is shown at 289. Although the symbol 289 is shown as a guard period, it has a small overlap 290 with the uplink symbol in the 60kHz parameter set, and therefore, OFDM symbol 289 may be used alternatively to send data in the downlink, with some interference. Fig.11 It is shown that the more frequently the self-contained TDD time intervals of the higher parameter set occur, the higher the number of OFDM symbols in the lower parameter set that need to be set as the guard period.

[0080] Figure 12 to Figure 14 Each shows a 0.25 ms time interval of a time-frequency resource with a different parameter set. At 312, a time-frequency resource with a subcarrier spacing of 30 kHz is shown, and at 314, a time-frequency resource with a subcarrier spacing of 60 kHz is shown. Fig.12 and Fig.13 Both the 30kHz parameter set and the 60kHz parameter set in have a self-contained TDD time interval of 0.25ms. Fig.14 There is a self-contained TDD time interval of 0.125ms for the 60kHz parameter set only. Fig.14 In the embodiment, whenever an OFDM symbol of the 30 kHz parameter set overlaps in time with an uplink OFDM symbol of the 60 kHz parameter set, the OFDM symbol of the 30 kHz parameter set is set as a guard period.

[0081] Symbol Alignment

[0082] Symbol alignment means that each symbol of the subframe corresponding to the minimum subcarrier spacing is aligned with an integer number of symbols of the subframe with a larger subcarrier spacing. The proportional relationship between the subcarrier spacing gives how many symbols of the larger subcarrier spacing will be aligned with the symbols of the smaller subcarrier spacing. Symbol alignment is applicable to long CP OFDM symbols and normal CP OFDM symbols, and if subframes of different parameter sets start at the same time in the TDD frame structure, symbol alignment allows subframe alignment.

[0083] There are some scenarios such as low latency applications where symbol alignment may be desirable. When symbol alignment exists, then it is easier to have a TTU of any duration for any parameter set. Furthermore, when symbol alignment exists, then it is easier to allow the TTU for each parameter set to vary over time. Furthermore, when symbol alignment exists, self-decodable OFDM symbols can be employed instead of encoding / decoding on a full TTU.

[0084] For the frequency interval f s =f0×2 n , where f0 is the reference frequency and f0 = 15kHz, then 2 n OFDM symbols are aligned with a 15kHz OFDM symbol. For example, when n=1, the frequency spacing is f s = 30kHz and 2 of the 30kHz parameter set 1 = 2 OFDM symbols are aligned with one OFDM symbol of the 15kHz parameter set. However, the presence of long CP OFDM symbols may complicate symbol alignment. Due to the presence of long CP OFDM symbols, not all symbols of one parameter set must be aligned with symbols of another parameter set. For example, returning to Figure 6 , although there is subframe alignment, there is not always symbol alignment between different parameter sets, as shown at 212.

[0085] However, an exemplary embodiment with symbol alignment is shown below. Furthermore, by reordering long CP OFDM symbols and regular CP OFDM symbols, a potentially efficient use of long CP OFDM symbols or additional portions of long CP OFDM symbols in a TDD architecture is possible.

[0086] Fig.15 and Fig.16 Each shows a 0.5 ms time interval of a time-frequency resource with a different parameter set. At 402, a time-frequency resource with a subcarrier spacing of 15 kHz is shown, and at 404, a time-frequency resource with a subcarrier spacing of 30 kHz is shown. Both the 15 kHz parameter set and the 30 kHz parameter set have a self-contained TDD time interval of 0.5 ms. Fig.15In the example shown in , a single long CP OFDM symbol 406 in the 15kHz parameter set is alternatively located immediately in front of the uplink OFDM symbol and replaced by a guard period. That is, a guard period equal to a single long CP OFDM symbol in the 15kHz parameter set appears at symbol index #5, rather than having a single long CP OFDM symbol at index #0. Index #0 alternatively includes a conventional CP OFDM symbol. In addition, two long CP OFDM symbols 408 in the 30kHz parameter set are located immediately in front of the uplink OFDM symbol and replaced by a guard period. All other OFDM symbols are conventional CP OFDM symbols. Symbol alignment can be achieved by moving the long CP OFDM symbols in the 30kHz parameter set adjacent to each other and located at the same position as the single long CP OFDM symbol in the 15kHz parameter set. In addition, by placing the long CP OFDM symbol immediately in front of the UL OFDM symbol, the long CP OFDM symbol can be replaced by a guard period. Therefore, the long CP OFDM symbol duration is used to provide a guard period that is 0.52 μs longer than the guard period that is equal to the conventional CP OFDM symbol in duration. Having a longer guard period can provide a more robust timing advance depending on the cell size. By having a longer guard period, there is more time available for timing advance for the UE to start their uplink transmission before the downlink phase begins. If the UE is far from the base station, for example, due to a large cell, then the UE may need a longer timing advance. Having a longer guard period can better accommodate longer timing advances. In addition, by using a long CP as part of the guard period, the overhead of having a long CP in data transmission can be alleviated.

[0087] exist Fig.16 In the example of , long CP OFDM symbols are not used. However, in order to be compatible with the LTE system using long CP OFDM symbols, a time portion equal to 0.52 μs is inserted before the uplink OFDM symbol, either inserted immediately before the uplink OFDM symbol (as shown in the figure), or inserted immediately after the downlink OFDM symbol, and the time portion equal to 0.52 μs is the extra length of the long CP relative to the conventional CP for 15 kHz. The duration of 0.52 μs is used as part of the guard period. The OFDM symbol in the 15 kHz parameter set located immediately before the uplink OFDM symbol is replaced by the guard period. Similarly, the two OFDM symbols in the 30 kHz parameter set located immediately before the uplink OFDM symbol are also replaced by the guard period.

[0088] although Fig.15 and Fig.16The guard period in the 30 kHz parameter set shown in comprises two OFDM symbols, alternatively a guard period comprising only one or more than two OFDM symbols may be used. In general, the number of uplink OFDM symbols and the number of OFDM symbols used as guard periods may vary.

[0089] Fig.17 Corresponds to Fig.15 , but it is for the case where the 30kHz parameter set is replaced by the 60kHz parameter set. 405 shows the time-frequency resources corresponding to the 60kHz parameter set. Fig.18 yes Fig.17 A variant of , in which only two long CP OFDM symbols in the 60kHz parameter set are used as a guard period located in front of the uplink OFDM symbol. The remaining two long CP OFDM symbols shown at 407 are used to send data in the downlink.

[0090] Fig.19 Corresponds to Fig.16 , but it is for the case where the 30kHz parameter set is replaced by the 60kHz parameter set. 405 shows the time-frequency resources corresponding to the 60kHz parameter set. Fig. 20 yes Fig.19 A variant of this, where the guard period in the 60 kHz parameter set includes only two regular CP OFDM symbols.

[0091] Fig.21 and Fig. 22 Corresponding to Fig.15 and Fig.16 , but it is for the case where 30kHz is chosen as the reference parameter set. Fig.21 and Fig. 22 Each shows a 0.25ms time interval of a time-frequency resource with symbol alignment of a different parameter set. A time-frequency resource with a subcarrier spacing of 30kHz is shown at 412, and a time-frequency resource with a subcarrier spacing of 60kHz is shown at 414. Both the 30kHz parameter set and the 60kHz parameter set have a self-contained TDD time interval of 0.25ms. Fig.21 In the example shown in , a single long OFDM symbol 416 in the 30kHz parameter set is placed immediately before the uplink OFDM symbol, i.e., at symbol index #5, rather than at symbol index #0, and is replaced by a guard period. Alternatively, symbol index #0 includes a regular CP OFDM symbol. Similarly, two long CP OFDM symbols 418 in the 60kHz parameter set are located immediately before the uplink OFDM symbol and are replaced by a guard period.

[0092] exist Fig. 22In the embodiment of the present invention, long CP OFDM symbols are not used. However, a time portion equal to 0.26 μs is inserted before the uplink OFDM symbol, either immediately before the uplink OFDM symbol as shown in the figure, or immediately after the downlink OFDM symbol, which is the extra length of the long CP relative to the conventional CP for 30 kHz. The duration of 0.26 μs is used as part of the guard period. The OFDM symbol in the 30 kHz parameter set immediately before the uplink OFDM symbol is replaced by the guard period. Similarly, the two OFDM symbols in the 60 kHz parameter set immediately before the uplink OFDM symbol are also replaced by the guard period.

[0093] Fig.23 A 0.5ms subframe of an OFDM symbol with different parameter sets is shown. A time-frequency resource with a subcarrier spacing of 15kHz is shown at 432, a time-frequency resource with a subcarrier spacing of 30kHz is shown at 434, and a time-frequency resource with a subcarrier spacing of 60kHz is shown at 436. Each subframe uses only regular CP OFDM symbols, so there is symbol alignment. However, in order to be compatible with LTE systems using long CP OFDM symbols, a time portion equal to 0.52μs is inserted at the beginning of each subframe, as shown at 438, and the time portion equal to 0.52μs is the additional length of the long CP relative to the regular CP used for 15kHZ subcarrier spacing. In one embodiment, no data transmission occurs during this time period. However, in other embodiments, such as in some FDD embodiments, data transmission may occur during the 0.52μs portion. The 0.52μs portion is equal to 16 T s , where T s is the sampling time and T s = FFT size / OFDM symbol duration. Figure 5 As can be seen in episode 2, for an FFT size of 2048 points, 66.66667 μs is the symbol duration for 15 kHz. s A sample occurs once every 1 μs, where 0.52 μs equals 16 T s 16 Ts appear at the beginning and can be used as part of the CP of the first symbol.

[0094] Alternatively, a time portion equal to 0.52 μs may be alternatively inserted at the end of each subframe. As shown at 440, a guard period is required when there is a transition from a downlink subframe to an uplink subframe, and vice versa. 0.52 μs is included as part of the guard period. Therefore, the 0.52 μs duration may be included as part of the required guard period between the uplink OFDM symbol and the downlink OFDM symbol in addition to being an overhead. Note that the time interval is scalable relative to 0.49949 ms rather than 0.5 ms. When seven 15 kHz OFDM symbols are defined as the subframe duration, then the 15 kHz, 30 kHz, and 60 kHz parameter sets will have scalable subframe durations of 0.49949 ms, 0.49949 / 2 ms, and 0.44949 / 4 ms, respectively.

[0095] In reference Figures 6 to 23 All of the embodiments described use some or all of the following parameter sets: 15kHz, 30kHz and 60kHz subcarrier spacing. However, all of these embodiments can be modified to use other parameter sets in a straightforward manner. For completeness, Figure 24 to Figure 27 Some examples involving 7.5kHz subcarrier spacing are shown in FIG. Figure 24 to Figure 27 Corresponding to Figures 17 to 20 , but with 7.5kHz and 30kHz parameter sets.

[0096] exist Fig.24 In the figure, time-frequency resources corresponding to the 7.5kHz parameter set are shown at 462, and time-frequency resources corresponding to the 30kHz parameter set are shown at 464. Fig.25 yes Fig.24 A variant of , in which only two long CP OFDM symbols in the 30kHz parameter set are used as a guard period preceding an uplink OFDM symbol. The other two long CP OFDM symbols shown at 467 are used to send data in the downlink.

[0097] exist Fig.26 , again, time-frequency resources corresponding to the 7.5 kHz parameter set are shown at 462, and time-frequency resources corresponding to the 30 kHz parameter set are shown at 464. Fig. 27 yes Fig.26 A variant of , where the guard period in the 30kHz parameter set includes only two regular CP OFDM symbols. Using 7.5kHz as the reference parameter set results in scaling of the additional CP. For example, relative to Fig.19 and Fig. 20 The 0.52μs strip in Fig.26 and Fig. 27As shown in , a strip of 1.04 μs is used as part of the guard period. 1.04 μs is equal to the additional duration of the long CP relative to the regular CP for 7.5 kHz subcarrier spacing.

[0098] In reference Figure 6 to Figure 27 In all the embodiments described, the downlink dominant subframe has been described. The same discussion also applies to the uplink dominant subframe. For example, Figure 6 to Figure 27 All the figures in can be modified to replace each uplink OFDM symbol with a downlink OFDM symbol and vice versa.

[0099] Fig.28 Describes general symbol misalignment. Fig.28 In the following description of some other figures, the terms "useful symbol duration" and "total symbol duration" are used. Useful symbol duration refers to the duration of an OFDM symbol minus the duration of a CP. The total symbol duration is the sum of the useful symbol duration and the CP duration.

[0100] Fig.28 A frame structure 500 is shown that carries symbols that are not aligned on sets of subcarrier frequencies having different subcarrier spacings. The frame structure 500 may include one or more subframes.

[0101] A series of OFDM symbols 501-514 are transmitted on subcarrier set 591 in frame 590. Frame 590 may include one or more subframes. A series of OFDM symbols 561-567 are also transmitted on subcarrier set 592 in frame 590. Each of symbols 501-514 includes a useful symbol portion 521-534 and a CP 541-554. The CP is shown in hatching. Similarly, each of symbols 561-567 includes a useful symbol portion 571-577 and a CP 581-587. The total symbol duration of each of symbols 501-514 is less than the total symbol duration of each of symbols 561-567 because the subcarrier spacing of subcarrier set 591 is greater than the subcarrier spacing of subcarrier set 592. In this example, the subcarrier spacing of subcarrier set 591 is twice the subcarrier spacing of subcarrier set 592. Therefore, the duration of each of the useful symbol portions 521-534 is half the duration of each of the useful symbol portions 571-577. Other examples are also possible. For example, the subcarrier spacing of subcarrier set 591 can be any integer multiple of the subcarrier spacing of subcarrier set 592.

[0102] In addition, the cyclic prefix 541 of the preamble symbol 501 has a longer duration than the cyclic prefixes 542-554 of the symbols 502-514. The long CP OFDM symbol 501 is represented using a hatching along the top of the OFDM symbol, as shown at 166. This long CP can help mitigate inter-symbol interference between the preamble symbol 501 in the frame 590 and the trailing symbol (i.e., the last symbol) in the frame before the frame 590. For similar reasons, the CP 581 of the preamble symbol 561 also has a longer duration than the cyclic prefixes 582-587 of the symbols 562-567.

[0103] The longer durations of CP 541 and CP 581 result in a pair of symbols 501 and 502 having a combined symbol duration that is different from the symbol duration of symbol 561. Therefore, as shown at 595, the rear edge of symbol 502 is misaligned with the rear edge of symbol 561. This misalignment also affects the alignment of subsequent symbols. For example, the misalignment between the rear edges of symbols 502 and 561 results in a pair of symbols 503 and 504 being misaligned with symbol 562, which in turn causes a pair of symbols 511 and 512 to be misaligned with symbol 566, which in turn causes a pair of symbols 513 and 514 to be misaligned with symbol 567.

[0104] Fig.29 Frame structure 600 is shown for a frame 690 carrying symbols aligned on a set of subcarrier frequencies having different subcarrier spacings. Frame 690 may include one or more subframes.

[0105] A series of OFDM symbols 601-614 are transmitted on subcarrier set 691, and a series of OFDM symbols 661-667 are transmitted on subcarrier set 692. The subcarrier spacing of subcarrier set 691 is greater than that of subcarrier set 692. For example, the subcarrier spacing of subcarrier 691 may be 60 kHz, and the subcarrier spacing of subcarrier 692 may be 30 kHz. Therefore, symbols 601-614 have a shorter useful symbol duration, cyclic prefix duration, and total symbol duration than symbols 661-667. However, in frame structure 600, the duration of cyclic prefix 631 of preamble symbol 601 is extended so that the trailing edge of symbol 602 is aligned with the trailing edge of symbol 661, as shown at 695. In an alternative embodiment, cyclic prefix 681 of preamble symbol 661 may be shortened so that the trailing edge of preamble symbol 661 is aligned with the trailing edge of symbol 602. As mentioned herein, the trailing edge of one symbol is "aligned" with the trailing edge of another symbol if the two symbols terminate within one basic time unit (Ts) of each other. The duration of the basic time unit may vary with different standard communication protocols. For example, the Fourth Generation Long Term Evolution (4G LTE) defines the basic time unit as 32.6 nanoseconds (ns).

[0106] By aligning symbol 601 and symbol 602 with symbol 661, the leading edge of symbol 603 is aligned with the leading edge of symbol 662. As mentioned herein, the leading edge of one symbol is "aligned" with the leading edge of another symbol if the respective symbol transmissions start within one basic time unit (Ts) of each other. In this embodiment, cyclic prefixes 633 and 634 of symbol 603 and symbol 604 have the same duration as cyclic prefix 632 of symbol 602, which is approximately equal to half the duration of cyclic prefix 682 of symbol 662. Therefore, the trailing edge of symbol 604 is aligned with the trailing edge of symbol 662. Symbols 611, 612, 613, and 614 have the same cyclic prefix duration as symbols 603 and symbol 604, and symbols 666 and symbol 667 have the same cyclic prefix duration as symbol 662. Therefore, symbols 611 and symbol 612 are aligned with symbol 666, and symbols 613 and symbol 614 are aligned with symbol 667.

[0107] Fig.306 is a close-up of how OFDM symbols 601, 602, 603, and 604 are aligned with symbols 661 and 662, with a scalability factor of 2 between the two parameter sets. In this example, CP1 is the duration of cyclic prefix 631 of preamble symbol 601, CP2 is the duration of cyclic prefix 632 of symbol 602, CP3 is the duration of cyclic prefix 681 of preamble symbol 661, and CP4 is the duration of cyclic prefix 682 of symbol 662. To ensure that the trailing edges of symbol 602 and symbol 661 are aligned in the time domain, the ratio of cyclic prefixes 631, 632, and 681 is set so that CP3=CP1+CP2. To ensure that the trailing edges of symbol 604 and symbol 662 are aligned in the time domain, the ratio of cyclic prefixes 633, 634, and 682 is set so that CP4=2*CP2.

[0108] Notice, Fig.30 can be regarded as equivalent to the above Fig.23 Described embodiment: Fig.23 The time band 438 in is Fig.30 The duration of CP1-CP2 in. Fig.30 (as well as Fig.31 ) in which CP3-CP4=CP1-CP2 is maintained, which is equal to Fig.23 0.52us in.

[0109] CP4 is twice as long as CP2 because Fig.30 The two parameter sets shown in FIG. 1 have subcarrier spacings that differ by a factor of two. In an alternative embodiment, reference Fig.31 , the subcarrier spacing of subcarrier 791 is four times that of subcarrier 792 (e.g., 60 kHz and 15 kHz). The ratio of cyclic prefixes 731, 732, 733, 734, and 781 is set so that CP3=CP1+3*CP2. To ensure that the trailing edges of symbol 708 and symbol 762 are aligned in the time domain, the ratio of cyclic prefixes 735, 736, 737, 738, and 782 is set so that CP4=4*CP2. Other configurations for aligning symbols of different ratios with different subcarrier spacings will be apparent to those skilled in the art.

[0110] In some embodiments, groups of two or more symbols aligned within the same frame may be scheduled independently of one another. For example, symbol 601 and symbol 602 may be assigned to one service stream, and symbols 603 and 604 may be assigned to another service stream. Similarly, symbol 661 and symbol 662 may be assigned to different service streams. It is further contemplated that groups of multiple symbols in a single subframe may be scheduled independently even if all symbols in the groupings are not aligned, as long as the start and end of the groups are aligned. For example, if cyclic prefix 681 is shortened and cyclic prefix 682 is extended by the same amount, the end of symbol 602 and symbol 661 will no longer be aligned, but the end of symbol 604 and symbol 662 will still be aligned. Additionally or alternatively, two or more symbols in the same subframe may have a longer cyclic prefix duration, as will be described below with reference to Fig.33 Just as described.

[0111] Symbols transmitted on subband sets with different subcarrier spacings may be aligned on a subframe, slot, or mini-slot basis. The number of shorter symbols aligned with a given longer symbol may vary based on the CP length of the corresponding symbol. Aligning subsets of symbols allows for higher granularity scheduling, which allows for lower latency data transmission. For example, data transmission may be scheduled in the middle of a frame at the point where the symbols are aligned, rather than on a frame-by-frame basis.

[0112] Fig.32Flowchart of an embodiment method 800 applicable to sending data, which can be performed by a transmitter. At step 810, the transmitter sends at least a first symbol and a second symbol on a first subcarrier set in a frame. The first symbol and the second symbol are consecutive symbols having the same useful symbol duration and different cyclic prefix durations in the time domain. At step 820, the transmitter sends at least a third symbol having a useful symbol duration different from the first symbol and the second symbol on a second carrier set in the frame, wherein the combined duration of the cyclic prefixes in the first symbol and the second symbol is within one basic time unit of the duration of the cyclic prefix in the second symbol. In one embodiment, another method for wireless communication is provided. The method includes sending a first subframe with a first subcarrier spacing. The first subframe includes a first plurality of symbols, the first plurality of symbols including a first symbol and a second symbol. The first symbol includes a first cyclic prefix having a first length, and the second symbol includes a second cyclic prefix having a second length shorter than the first length. The method also includes sending a second subframe with a second subcarrier spacing, the second subcarrier spacing being less than the first subcarrier spacing. The second subframe includes a second plurality of symbols, the second plurality of symbols including at least a third symbol and a fourth symbol. The third symbol includes a third cyclic prefix having a third length, and the fourth symbol includes a fourth cyclic prefix. In any embodiment, the first, second, third, and fourth cyclic prefixes are configured such that the end of at least one symbol in the first subframe is aligned in time with the end of at least one symbol in the second subframe.

[0113] Some embodiments may transmit symbols at subcarrier frequencies with subcarrier spacing of 15kHz, 30kHz, and / or 60kHz. The useful symbol duration for 15kHz, 30kHz, and 60kHz subcarrier spacing may be 2048 basic time units, 1024 basic time units, and 512 basic time units, respectively.

[0114] Fig.33 is a diagram of an embodiment of a frame structure for transmitting symbols on a subcarrier frequency set with subcarrier spacing of 15 kHz and 30 kHz. In this example, the frame duration is based on using the 15 kHz parameter set as the reference parameter set. Fig.33 In (and Figures 34 to 37 The hatching in the middle indicates the presence of a long CP OFDM symbol, which is located at Fig.33 The shaded area can be used to send data.

[0115] The first 15kHz symbol and the eighth 15kHz symbol in a frame have a cyclic prefix duration of 160 basic time units, and the other 15kHz symbols have a cyclic prefix duration of 144 basic time units. The first 30kHz symbol in a frame and the fifteenth 30kHz symbol in a frame have a cyclic prefix duration of 88 basic time units, and the other 30kHz symbols have a cyclic prefix duration of 72 basic time units. It is contemplated that symbols with longer cyclic prefix durations may alternatively be located elsewhere in the corresponding subframe. For example, if the nth 15kHz symbol and the (2n-1)th 30kHz symbol have a longer cyclic prefix duration, each pair of 30kHz symbols will still be aligned with each 15kHz symbol.

[0116] Fig.34 is a diagram of an embodiment of a frame structure for transmitting symbols on a subcarrier frequency set with subcarrier spacing of 15 kHz and 30 kHz. In this example, the frame duration is based on the 30 kHz parameter set as the reference parameter set. The first 15 kHz symbol in each 0.5 ms frame has a cyclic prefix duration of 160 basic time units, and the other 15 kHz symbols have a cyclic prefix duration of 144 basic time units. The first 30 kHz symbol in each 0.5 ms frame has a cyclic prefix duration of 88 basic time units, and the other 30 kHz symbols have a cyclic prefix duration of 72 basic time units.

[0117] exist Fig.34 In an alternative embodiment to the embodiment shown in FIG. 1 , the first OFDM symbol with a longer CP may only appear once every 1 ms instead of once every 0.5 ms. If the additional CP portion instead appears once every 1 ms, then Fig.34 The extra part of the long CP of the 8th symbol of the 15kHz interval will be appended to the first OFDM symbol instead, and the 8th symbol will have the same CP length as the other OFDM symbols except the first OFDM symbol instead. The 30kHz interval will have a similar structure, that is, the long strips are grouped at the beginning of every 1ms.

[0118] Fig.35is a diagram of an embodiment of a frame structure for sending symbols on a subcarrier frequency set with a subcarrier spacing of 30kHz and 60kHz. In this example, the frame duration is based on a 30kHz parameter set. The first 30kHz symbol of each 0.5ms frame has a cyclic prefix duration of 88 basic time units, and the other 30kHz symbols have a cyclic prefix duration of 72 basic time units. The first 60kHz symbol of each 0.5ms frame has a cyclic prefix duration of 52 basic time units, and the other 60kHz symbols have a cyclic prefix duration of 36 basic time units. In an alternative embodiment, a 0.5ms frame based on a 30kHz parameter set may include two 30kHz symbols with a cyclic prefix duration of 80 basic time units, 12 30kHz symbols with a cyclic prefix duration of 72 basic time units, two 60kHz symbols with a cyclic prefix duration of 44 basic time units, and 24 60kHz symbols with a cyclic prefix duration of 36 basic time units. Each 30kHz symbol with a cyclic prefix duration of 80 basic time units may be aligned with a pair of 60kHz symbols, the pair of 60kHz symbols including one 60kHz symbol with a cyclic prefix duration of 44 basic time units and one 60kHz symbol with a cyclic prefix duration of 36 basic time units. Each 30kHz symbol with a cyclic prefix duration of 72 basic time units may be aligned with a pair of 60kHz symbols, the pair of 60kHz symbols both having a cyclic prefix duration of 36 basic time units.

[0119] Fig.36 is a diagram of an embodiment of a frame structure for transmitting symbols on a subcarrier frequency set with subcarrier spacing of 30 kHz and 60 kHz. In this example, the frame duration is based on the 60 kHz parameter set. The first 30 kHz symbol of each 0.25 ms frame has a cyclic prefix duration of 80 basic time units, and the other 30 kHz symbols have a cyclic prefix duration of 72 basic time units. The first 60 kHz symbol of each 0.25 ms frame has a cyclic prefix duration of 44 basic time units, and the other 60 kHz symbols have a cyclic prefix duration of 36 basic time units.

[0120] Other settings can be envisioned. For example, cyclic prefixes with different lengths can allow more symbols to be included in a subframe compared to the ratio corresponding to the subcarrier spacing, which results in higher spectral efficiency and alignment of the start of at least the first symbol and the end of the last symbol in each parameter set. Table 1 below shows some exemplary parameter sets. It can be seen that in some embodiments, 14 symbols with a 15kHz subcarrier spacing can be aligned with more than 28 symbols with a 30kHz subcarrier spacing, or with more than 56 symbols with a 60kHz subcarrier spacing. In other embodiments, 28 symbols with a 30kHz subcarrier spacing can be aligned with more than 56 symbols with a 60kHz subcarrier spacing. As shown in the example in Table 1, a subframe of 1ms can be configured with 56, 57, 58 or 59 symbols with a 60kHz subcarrier spacing (SCS) and different CP overheads, and can be aligned with a subframe of 14 symbols with a 15kHz SCS and a normal CP. It can also be aligned with a subframe of 28 or 29 symbols with a 30kHz SCS and different CP overheads. Other arrangements are possible, including smaller subcarrier spacings, such as 3.75 kHz or 7.5 kHz, and larger subcarrier spacings, such as 120 kHz.

[0121]

[0122] Table 1

[0123] Fig.37 1 is a diagram of an embodiment of a frame structure for transmitting symbols on a subcarrier frequency set having subcarrier spacings of 15 kHz, 30 kHz, and 60 kHz. In this example, the frame duration is based on a 60 kHz parameter set. In this example, the first 15 kHz symbol of every other frame is not aligned with the first 30 kHz symbol and 60 kHz symbol in those frames.

[0124] Offset between different subframes

[0125] Symbol alignment is discussed in some of the embodiments above. However, even if symbol alignment can exist between different time-frequency resource sets, the symbol at the start of a subframe in one time-frequency resource set may be different from the symbol at the start of a subframe in another time-frequency resource set. That is, index 0 of a subframe of one time-frequency resource set may not be aligned with index 0 of a subframe of another time-frequency resource set. Even when two time-frequency resource sets have the same parameter set, index 0 of a subframe of one time-frequency resource set may not be aligned with index 0 of a subframe of another time-frequency resource set. This is because two subframes belonging to the same parameter set may still have different durations. For example, a 15kHz subframe in an LTE system has 14 OFDM symbols, and the 14 OFDM symbols include 2 time slots of 7 OFDM symbols respectively, while subframes in non-LTE systems may have different numbers of OFDM symbols, such as 7 OFDM symbols. The start time between LTE subframes and non-LTE subframes may be misaligned, depending on the position of the long CP OFDM symbol. In a TDD frame structure, this can potentially be the case when long CP symbols are used as a guard period and may not be mapped at the beginning. However, in an FDD frame structure where a guard period is not required, symbol alignment is equivalent to subframe alignment when different systems have the same position / index of long CP symbols relative to the subframe. For example, in FDD, one LTE subframe of 14 symbols can be both symbol-aligned and subframe-aligned with two subframes of 7 symbols of a non-LTE 15kH subframe, where the first symbol in each subframe is a long CP symbol.

[0126] Typically, the starting symbol of a subframe of one time-frequency resource set may be offset by P symbols relative to the starting symbol of a subframe of another time-frequency resource set. P is configurable. This offset is more meaningful in a TDD architecture for the reasons mentioned in the previous paragraph.

[0127] Fig.38 A first set of time-frequency resources 902 and a second set of time-frequency resources 904 are shown. The transmissions in each of the first set of time-frequency resources 902 and the second set of time-frequency resources 904 are symbol aligned. As shown in some previous figures, the cross-hatching on the top of the OFDM symbol indicates that the OFDM symbol is a long CP OFDM symbol. Although the time-frequency resources 902 and 904 are symbol aligned, the index 0 of the subframe of resource 902 is offset by 5 OFDM symbols relative to the index 0 of resource 904, i.e., P=5. Fig.38 The number of symbols in each subframe in different resource sets 902 and 904 is only an example.

[0128] As explained previously, some embodiments set the cyclic prefix duration of the leading and trailing symbols so that the longer symbols are aligned in time with a grouping of two or more shorter symbols. Some embodiments set the cyclic prefix duration of symbols sent on carriers with different subcarrier spacings in a manner such that each longer duration symbol is aligned with a group of one or more shorter duration symbols.

[0129] Other methods

[0130] Back to Figure 1 , the location of specific uplink OFDM symbols and downlink OFDM symbols in each subframe is determined in advance or semi-statically according to the subframe structure to obtain the subframe and / or symbol alignment discussed above. The instructions are then stored in a memory in each of the UEs 106a-c and the base station 104. The instructions indicate the OFDM symbol time interval, the location of the guard period, and whether the OFDM symbol is for uplink or downlink communication. The scheduler 110 in the base station 104 then schedules the UE on the resources.

[0131] Specific embodiments are described above. More generally, a method performed by an apparatus in a wireless communication system is provided. The wireless communication system may be a TDD system. An apparatus for performing the method is also disclosed. The apparatus may be a UE or a base station. In one embodiment, a method includes sending and receiving data using one of a first time-frequency resource set and a second time-frequency resource set. The frequency spacing between subcarriers of an OFDM symbol of the first time-frequency resource set is different from the frequency spacing between subcarriers of an OFDM symbol of the second time-frequency resource set. The transmissions on the first time-frequency resource set and the second time-frequency resource set are subframe aligned. When the first time-frequency resource set carries one or more downlink OFDM symbols, the downlink OFDM symbols carried by the first time-frequency resource set overlap in time with at least one of the following: the downlink OFDM symbols carried by the second time-frequency resource set and the guard period in the second time-frequency resource set. When the first time-frequency resource set carries one or more uplink OFDM symbols, the uplink OFDM symbols carried by the first time-frequency resource set overlap in time with at least one of the following: the uplink OFDM symbols carried by the second time-frequency resource set and the guard period in the second time-frequency resource set.

[0132] In some embodiments, for example Figure 7 , for a specific duration: the first time-frequency resource set includes a first guard period, the first guard period is inserted between the first downlink OFDM symbol and the first uplink OFDM symbol; the second time-frequency resource set includes a second guard period, the second guard period is inserted between the second downlink OFDM symbol and the second uplink OFDM symbol. The first guard period and the second guard period start at different times but end at the same time.

[0133] In some embodiments, for example Figures 8 to 11 and Fig.14 , for a specific duration: the first time-frequency resource set carries an uplink OFDM symbol and a downlink OFDM symbol; the second time-frequency resource set carries only a downlink OFDM symbol and one or more guard periods; the uplink OFDM symbol carried by the first time-frequency resource set overlaps in time with the guard period of the second time-frequency resource set. In some embodiments, when GP 286 is replaced by an OFDM symbol, another uplink OFDM symbol carried by the first time-frequency resource set may partially overlap with a downlink OFDM symbol carried by the second time-frequency resource set, for example Figure 8 as shown in .

[0134] In some embodiments, for a specific duration: the first time-frequency resource set carries uplink OFDM symbols and downlink OFDM symbols; the second time-frequency resource set carries only uplink OFDM symbols and one or more protection periods; the downlink OFDM symbols carried by the first time-frequency resource set overlap in time with the protection period carried by the second time-frequency resource set.

[0135] In some embodiments, for example, Figure 7 As shown in , a third time-frequency resource set is also used, and the third time-frequency resource set has a subcarrier frequency spacing that is different from the subcarrier frequency spacing of the first time-frequency resource set and the second time-frequency resource set. The third time-frequency resource set carries a transmission, and the transmission is aligned with the transmission subframes of the first time-frequency resource set and the second time-frequency resource set. When the first time-frequency resource set carries one or more downlink OFDM symbols, the downlink OFDM symbols carried by the first time-frequency resource set also overlap in time with at least one of the downlink OFDM symbols and the protection period of the third time-frequency resource set. When the first time-frequency resource set carries one or more uplink OFDM symbols, the uplink OFDM symbols in the first time-frequency resource set overlap in time with at least one of the downlink OFDM symbols and the protection period in the third time-frequency resource set.

[0136] In some embodiments, another method performed by an apparatus includes sending and receiving data according to a time-frequency resource set. The time-frequency resource set includes: a plurality of time durations, each time duration having a length of t R , each duration used to send or receive is of length t R A single regular CP OFDM symbol; a guard period, during which no data is transmitted. The guard period is inserted between downlink transmission and uplink transmission. The duration of the guard period is t G ≥t L , where t L is equal to the duration of a single long CPOFDM symbol, and where t L >tR When a guard period is "inserted between" an uplink transmission (e.g., an uplink OFDM symbol) and a downlink transmission (e.g., a downlink OFDM symbol), this means that the uplink transmission may precede the downlink transmission, or vice versa. A guard period inserted between a downlink transmission and an uplink transmission has the same meaning as a guard period inserted between an uplink transmission and a downlink transmission, and there is no implied order: the downlink may precede the uplink, and vice versa.

[0137] In some embodiments, for example, Fig.15 , Fig.17 , Fig.18 and Fig.21 , the protection period has a length of t G = k × t L duration, where k is an integer and k ≥ 1. A guard period can be inserted with a duration of t R The downlink conventional CP OFDM symbol and duration is t R Between uplink conventional CP OFDM symbols. Fig.18 As shown in FIG, immediately before the guard period, there may be a period of length t for transmitting a single long CP OFDM symbol. L duration, and immediately following the guard period there may be a length of t for transmitting a single regular CP OFDM symbol R duration.

[0138] In some embodiments, when the subcarrier spacing of the OFDM symbol is 7.5 kHz, t L =t R +1.04μs; when the subcarrier spacing of the OFDM symbol is 15kHz, t L =t R +0.52μs; when the subcarrier spacing of the OFDM symbol is 30kHz, t L =t R +0.26μs; and when the subcarrier spacing of the OFDM symbol is 60kHz, t L =t R +0.13μs.

[0139] In some embodiments, a guard period is inserted with a duration of t R The downlink conventional CP OFDM symbol and duration is t R The uplink conventional CP OFDM symbols are separated by a guard period having a length of t G = k × t R +t E duration, where k is an integer and k ≥ 0, and where t Eis the duration of the extra CP between the long CP OFDM symbol and the regular CP OFDM symbol for the coexistence parameter set with the lowest subcarrier spacing. Fig.19 The coexistence parameter set with the lowest subcarrier spacing is 15kHz. For 15kHz, the additional CP is 0.52μs, so t E =0.52μs. As another example, Fig.26 The coexistence parameter set with the lowest subcarrier spacing is 7.5kHz. For 7.5kHz, the additional CP is 1.04μs, so t E =1.04μs. Alternatively, if the coexistence parameter set with the lowest subcarrier spacing is 30kHz, then t E will be equal to 0.26μs, and so on.

[0140] In some embodiments, for example, Fig.28 In the embodiment, the time-frequency resource set is a first time-frequency resource set, the transmission on the first time-frequency resource set is aligned with the transmission symbol on the second time-frequency resource set, and the first OFDM symbol in the subframe of the first time-frequency resource set is not aligned with the first OFDM symbol in the subframe of the second time-frequency resource set.

[0141] Other Systems

[0142] Fig.39 1 is a block diagram of an embodiment processing system 1100 for executing the methods described herein, which may be installed in a host device. As shown, the processing system 1100 includes a processor 1104, a memory 1106, and interfaces 1110-1114, which may or may not be Fig.39 Arranged as shown. Processor 1104 can be any component or collection of components suitable for performing computing and / or other processing-related tasks, and memory 1106 can be any component or collection of components suitable for storing programming and / or instructions executed by processor 1104. In one embodiment, memory 1106 includes a non-transitory computer-readable medium. Interfaces 1110, 1112, 1114 can be any component or collection of components that allow processing system 1100 to communicate with other devices / components and / or users. For example, one or more of interfaces 1110, 1112, 1114 can be suitable for transmitting data, control or management messages from processor 1104 to applications installed on a host device and / or a remote device. As another example, one or more of interfaces 1110, 1112, 1114 can be suitable for allowing a user or user device (e.g., a personal computer (PC), etc.) to interact / communicate with processing system 1100. Processing system 1100 may include Fig.39 Additional components not shown, such as long-term storage (e.g., non-volatile memory), etc.

[0143] In some embodiments, the processing system 1100 is included in a network device that accesses a telecommunication network or is part of a telecommunication network. In one example, the processing system 1100 is located in a network-side device in a wireless or wired telecommunication network, such as a base station, a relay station, a scheduler, a controller, a gateway, a router, an application server, or any other device in a telecommunication network. In other embodiments, the processing system 1100 is located in a user-side device that accesses a wireless or wired telecommunication network, such as a mobile station, a user equipment (UE), a personal computer (PC), a tablet computer, a wearable communication device (e.g., a smart watch, etc.), or any other device suitable for accessing a telecommunication network.

[0144] In some embodiments, one or more of interfaces 1110, 1112, 1114 connects processing system 1100 to a transceiver suitable for sending and receiving signaling over a telecommunications network.

[0145] Fig.40 1 is a block diagram of a transceiver 1200 suitable for sending and receiving signaling through a telecommunications network. The transceiver 1200 can be installed in a host device. As shown, the transceiver 1200 includes a network side interface 1202, a coupler 1204, a transmitter 1206, a receiver 1208, a signal processor 1210, and a device side interface 1212. The network side interface 1202 may include any component or component set suitable for sending or receiving signaling through a wireless or wired telecommunications network. The coupler 1204 may include any component or component set suitable for facilitating bidirectional communication on the network side interface 1202. The transmitter 1206 may include any component or component set suitable for converting a baseband signal into a modulated carrier signal suitable for sending through the network side interface 1202, such as an upconverter, a power amplifier, etc. The receiver 1208 may include any component or component set suitable for converting a carrier signal received through the network side interface 1202 into a baseband signal, such as a downconverter, a low noise amplifier, etc. The signal processor 1210 may include any component or collection of components suitable for converting baseband signals into data signals suitable for transmission through the device-side interface 1212, and vice versa. The device-side interface 1212 may include any component or collection of components suitable for transmitting data signals between the signal processor 1210 and components within a host device such as the processing system 600, a local area network (LAN) port, etc.

[0146] The transceiver 1200 may send and receive signaling via any type of communication medium. In some embodiments, the transceiver 1200 sends and receives signaling via a wireless medium. For example, the transceiver 1200 may be a wireless transceiver suitable for communicating according to a wireless telecommunication protocol, such as a cellular protocol, such as long term evolution (LTE), a wireless local area network (WLAN) protocol, such as Wi-Fi, or any other type of wireless protocol, such as Bluetooth, near field communication (NFC), etc. The network side interface 1202 may include one or more antennas / radiating elements. For example, the network side interface 1202 may include a single antenna, multiple separate antennas, or a multi-antenna array configured for multi-layer communication (e.g., single input multiple output (SIMO), multiple input single output (MISO), multiple input multiple output (MIMO), etc.). In other embodiments, the transceiver 1200 sends and receives signaling via a wired medium (e.g., twisted pair cable, coaxial cable, optical fiber, etc.). A particular processing system and / or transceiver may utilize all of the components shown, or only a subset of the components, and the level of integration may vary from device to device.

[0147] Other methods and systems

[0148] Fig.41 is an example method for transmitting data in a wireless communication system. In step 1302, k consecutive OFDM symbols are transmitted. The k consecutive OFDM symbols have a first subcarrier spacing. The duration of the first OFDM symbol of the k consecutive OFDM symbols is t1, and the durations of the remaining OFDM symbols of the k consecutive OFDM symbols are all t2<t1. The total duration of the k consecutive OFDM symbols is T ms. In step 1304, n>k consecutive OFDM symbols are transmitted. The n consecutive OFDM symbols have a second subcarrier spacing greater than the first subcarrier spacing. The duration of the first OFDM symbol of the n consecutive OFDM symbols is t3, and the durations of the remaining OFDM symbols of the n consecutive OFDM symbols are all t4<t3. The total duration of the n consecutive OFDM symbols is T ms.

[0149] The above about Fig.41 The described method will be referred to as Example 1. The following other examples are contemplated.

[0150] Example 2: The method according to Example 1, wherein T = 0.5 ms.

[0151] Example 3: The method according to Example 1, wherein T = 0.25 ms.

[0152] Example 4: The method according to any one of Examples 1 to 3, wherein the n consecutive OFDM symbols and the k consecutive OFDM symbols are transmitted simultaneously.

[0153] Example 5: A method according to any one of Examples 1 to 4, wherein the k consecutive OFDM symbols are sent on a first subcarrier set with the first subcarrier spacing, and wherein the n consecutive OFDM symbols are sent on a second subcarrier set with the second subcarrier spacing.

[0154] Example 6: The method of Example 5, wherein the first set of subcarriers and the second set of subcarriers belong to different carriers.

[0155] Example 7: The method of Example 5, wherein the first set of subcarriers and the second set of subcarriers belong to the same carrier.

[0156] Example 8: A method according to any one of Examples 1 to 7, wherein the first subcarrier spacing is 15 kHz and the second subcarrier spacing is 30 kHz.

[0157] Example 9: A method according to any one of Examples 1 to 7, wherein the first subcarrier spacing is 30 kHz and the second subcarrier spacing is 60 kHz.

[0158] Example 10: The method of any one of Examples 1 to 7, wherein k=7 and n=14.

[0159] Example 11: A method according to any one of Examples 1 to 10, wherein: the first OFDM symbol of the k consecutive OFDM symbols has a cyclic prefix, which is longer than the cyclic prefix of each of the remaining OFDM symbols of the k consecutive OFDM symbols; and the first OFDM symbol of the n consecutive OFDM symbols has a cyclic prefix, which is longer than the cyclic prefix of each of the remaining OFDM symbols of the n consecutive OFDM symbols.

[0160] Example 12: A method according to any one of Examples 1 to 11, wherein a rear edge of the first OFDM symbol of the k consecutive OFDM symbols is aligned with a rear edge of the second OFDM symbol of the n consecutive OFDM symbols.

[0161] Example 13: A method according to any one of Examples 1 to 12, wherein the second subcarrier spacing is an integer multiple of the first subcarrier spacing.

[0162] Example 14: The method of Example 13, wherein the integer multiple is a power of two.

[0163] Example 15: A method according to any one of Examples 1 to 14, wherein the first subcarrier spacing is 15 kHz×2 i, wherein i is an integer and i ≥ 0, and wherein the second subcarrier spacing is 15 kHz × 2 j , where j is an integer and j>i.

[0164] Example 16: A method according to any one of Examples 1 to 15, wherein the method is performed by a base station.

[0165] Example 17: A method according to any one of Examples 1 to 15, wherein the method is performed by a UE.

[0166] Example 18: A transmitter (which may be part of a base station or UE), or a base station, or a UE, for performing a method as described in any one of Examples 1 to 15.

[0167] Example 19: An apparatus having a memory and at least one processor, the at least one processor being operable to execute instructions stored in the memory so that the apparatus performs the method of any one of Examples 1 to 15. The apparatus may be a transmitter (which may be part of a base station or a UE), or the apparatus may be a base station or a UE.

[0168] Example 20: A transmitter is used to: send k consecutive OFDM symbols with a first subcarrier spacing, the first OFDM symbol of the k consecutive OFDM symbols has a duration t1, the remaining OFDM symbols of the k consecutive OFDM symbols all have a duration t2<t, and the total duration of the k consecutive OFDM symbols is T ms; send n>k consecutive OFDM symbols with a second subcarrier spacing, the second subcarrier spacing is larger than the first subcarrier spacing, the first OFDM symbol of the n consecutive OFDM symbols has a duration t3, the remaining OFDM symbols of the n consecutive OFDM symbols all have a duration t4<t3, and the total duration of the n consecutive OFDM symbols is T ms.

[0169] Example 21: A transmitter according to Example 20, wherein T = 0.5 ms.

[0170] Example 22: A transmitter according to Example 20, wherein T = 0.25 ms.

[0171] Example 23: A transmitter according to any one of Examples 20 to 22, wherein the transmitter is used to send n consecutive OFDM symbols and the k consecutive OFDM symbols simultaneously.

[0172] Example 24: A transmitter according to Examples 20 to 23, wherein the transmitter is used to send the k consecutive OFDM symbols on a first subcarrier set with the first subcarrier spacing, and is used to send the n consecutive OFDM symbols on a second subcarrier set with the second subcarrier spacing.

[0173] Example 25: The transmitter of Example 24, wherein the first set of subcarriers and the second set of subcarriers belong to different carriers.

[0174] Example 26: The transmitter of Example 24, wherein the first set of subcarriers and the second set of subcarriers belong to the same carrier.

[0175] Example 27: A transmitter according to any one of Examples 20 to 26, wherein the first subcarrier spacing is 15kHz and the second subcarrier spacing is 30kHz.

[0176] Example 28: A transmitter according to any one of Examples 20 to 26, wherein the first subcarrier spacing is 30 kHz and the second subcarrier spacing is 60 kHz.

[0177] Example 29: A transmitter according to any one of Examples 20 to 26, wherein k=7 and n=14.

[0178] Example 30: A transmitter according to any one of Examples 20 to 29, wherein: the first OFDM symbol of the k consecutive OFDM symbols has a cyclic prefix, which is longer than the cyclic prefix of each of the remaining OFDM symbols of the k consecutive OFDM symbols; and the first OFDM symbol of the n consecutive OFDM symbols has a cyclic prefix, which is longer than the cyclic prefix of each of the remaining OFDM symbols of the n consecutive OFDM symbols.

[0179] Example 31: A transmitter according to any one of Examples 20 to 30, wherein a rear edge of the first OFDM symbol of the k consecutive OFDM symbols is aligned with a rear edge of the second OFDM symbol of the n consecutive OFDM symbols.

[0180] Example 32: A transmitter according to any one of Examples 20 to 31, wherein the second subcarrier spacing is an integer multiple of the first subcarrier spacing.

[0181] Example 33: A transmitter according to Example 32, wherein the integer multiple is a power of two.

[0182] Example 34: A transmitter according to any one of Examples 20 to 33, wherein the first subcarrier spacing is 15kHz×2 i, wherein i is an integer and i ≥ 0, and wherein the second subcarrier spacing is 15 kHz × 2 j , where j is an integer and j>i.

[0183] Example 35: A transmitter according to any one of Examples 20 to 34, wherein the transmitter is part of a base station.

[0184] Example 36: A transmitter according to any one of Examples 20 to 35, wherein the transmitter is part of a UE.

[0185] Fig.42 The method is an exemplary method for transmitting data in a wireless communication system. In step 1402, an OFDM symbol is generated. Step 1402 is optional. The method may alternatively start at step 1404. In step 1404, a subcarrier spacing of 15 kHz×2 n k consecutive OFDM symbols are sent on a subcarrier set of n. n is an integer and n≥1. The duration of the first OFDM symbol of the k consecutive OFDM symbols is t1, and the remaining OFDM symbols of the k consecutive OFDM symbols all have a duration t2<t1. The total duration of the k consecutive OFDM symbols is T ms, where T=0.5ms or T=0.25ms.

[0186] The above about Fig.42 The described method will be referred to as Example 37. The following other examples are contemplated.

[0187] Example 38: The method of Example 37, wherein the first OFDM symbol has a cyclic prefix that is longer than a cyclic prefix of each of the remaining OFDM symbols.

[0188] Example 39: A method according to Example 37 or 38, wherein n=1, so that the subcarrier spacing is 30kHz.

[0189] Example 40: A method according to any one of Examples 37 to 39, wherein the method is performed by a base station.

[0190] Example 41: A method according to any one of Examples 37 to 39, wherein the method is performed by a user equipment (UE).

[0191] Example 42: A transmitter (which may be part of a base station or UE), or a base station, or a UE, for performing a method according to any one of Examples 37 to 39.

[0192] Example 43: An apparatus having a memory and at least one processor, wherein the at least one processor is operable to execute instructions stored in the memory so that the apparatus performs the method of any one of Examples 37 to 39. The apparatus may be a transmitter (which may be part of a base station or a UE), or the apparatus may be a base station or a UE.

[0193] Example 44: A transmitter for: transmitting a signal with a subcarrier spacing of 15 kHz × 2 n k consecutive OFDM symbols are sent on a subcarrier set, where n is an integer and n≥1; the first OFDM symbol of the k consecutive OFDM symbols has a duration t1, the remaining OFDM symbols of the k consecutive OFDM symbols all have a duration t2<t1, and the total duration of the k consecutive OFDM symbols is 0.5ms.

[0194] Example 45: The transmitter of Example 44, wherein the first OFDM symbol has a cyclic prefix that is longer than a cyclic prefix of each of the remaining OFDM symbols.

[0195] Example 46: A transmitter according to any one of Examples 44 or 45, wherein n=1, so that the subcarrier spacing is 30kHz.

[0196] Example 47: A transmitter according to any one of Examples 44 to 46, wherein the transmitter is part of a base station.

[0197] Example 48: A transmitter according to any one of Examples 44 to 46, wherein the transmitter is part of a user equipment (UE).

[0198] Fig.43 is an exemplary method for sending data in a wireless communication system. In step 1502, an OFDM symbol is generated. Step 1502 is optional. The method may alternatively start at step 1504. In step 1504, the multiple OFDM symbols are sent according to a frame structure. The frame structure includes k>1 consecutive OFDM symbol durations, followed by j>1 consecutive OFDM symbol durations. The k consecutive OFDM symbol durations and the j consecutive OFDM symbol durations are located in the same subframe. Each of the k consecutive OFDM symbol durations has a duration t1 and a first cyclic prefix (CP) length. Each of the j consecutive OFDM symbol durations has a duration t2>t1 and has a second CP length that is longer than the first CP length.

[0199] The above about Fig.43 The described method will be referred to as Example 49. Other examples are contemplated below.

[0200] Example 50: The method of Example 49, wherein at least some of the j consecutive OFDM symbol durations form a guard period in the subframe.

[0201] Example 51: A method according to Example 50, wherein all of j consecutive OFDM symbol durations form a guard period in the subframe.

[0202] Example 52: A method according to any one of Examples 49 to 51, wherein the k consecutive OFDM symbol durations are located at the beginning of a subframe.

[0203] Example 53: A method according to any one of Examples 49 to 52, wherein the multiple OFDM symbols are a first multiple OFDM symbols having a first subcarrier spacing, and the method further includes: sending a second multiple OFDM symbols having a second subcarrier spacing, wherein the transmitted OFDM symbols in the second multiple OFDM symbols have a duration that is an integer multiple of the duration of the OFDM symbols transmitted simultaneously in the first multiple OFDM symbols.

[0204] Example 54: A method according to Example 53, wherein the second subcarrier spacing is 15kHz×2 i , where i is an integer and i ≥ 0, and where the first subcarrier spacing is 15 kHz × 2 m , where m is an integer and m>i.

[0205] Example 55: A method according to Example 54, wherein the second subcarrier spacing is 15kHz and the first subcarrier spacing is 60kHz.

[0206] Example 56: A transmitter (which may be part of a base station or UE), or a base station, or a UE, for performing a method according to any one of Examples 49 to 55.

[0207] Example 57: An apparatus having a memory and at least one processor, wherein the at least one processor is operable to execute instructions stored in the memory so that the apparatus performs the method according to any one of Examples 49 to 55. The apparatus may be a transmitter (which may be part of a base station or a UE), or the apparatus may be a base station or a UE.

[0208] Example 58: A transmitter, used to: optionally generate multiple OFDM symbols; send the multiple OFDM symbols according to a frame structure, the frame structure comprising: k>1 consecutive OFDM symbol durations, followed by j>1 consecutive OFDM symbol durations; the k consecutive OFDM symbol durations and the j consecutive OFDM symbol durations are located in the same subframe, and each of the k consecutive OFDM symbol durations has a duration t1 and a first cyclic prefix (CP) length, and each of the j consecutive OFDM symbol durations has a duration t2>t1 and a second CP length longer than the first CP length.

[0209] Example 59: The transmitter of Example 58, wherein at least some of the j consecutive OFDM symbol durations form a guard period in the subframe.

[0210] Example 60: A transmitter according to Example 59, wherein all of j consecutive OFDM symbol durations form a guard period in the subframe.

[0211] Example 61: A transmitter according to any one of Examples 58 to 60, wherein the k consecutive OFDM symbol durations are located at the beginning of the subframe.

[0212] Example 62: A transmitter according to any one of Examples 58 to 61, wherein the multiple OFDM symbols are a first multiple OFDM symbols having a first subcarrier spacing, and the transmitter is also used to: send a second multiple OFDM symbols having a second subcarrier spacing, wherein the transmitted OFDM symbols in the second multiple OFDM symbols have a duration that is an integer multiple of the duration of simultaneously transmitted OFDM symbols in the first multiple OFDM symbols.

[0213] Example 63: The transmitter of Example 62, wherein the second subcarrier spacing is 15 kHz×2 i , where i is an integer and i ≥ 0, and where the first subcarrier spacing is 15 kHz × 2 m , where m is an integer and m>i.

[0214] Example 64: A transmitter according to Example 63, wherein the second subcarrier spacing is 15kHz and the first subcarrier spacing is 60kHz.

[0215] Further examples are contemplated below.

[0216] Example 65: At least a first symbol and a second symbol are sent on a first set of subcarriers in a frame. The first symbol and the second symbol are symbols that are consecutive in the time domain. The first symbol and the second symbol have the same useful symbol duration and different cyclic prefix durations. At least a third symbol is sent on a second set of subcarriers in a frame. The third symbol has a different useful symbol duration than the first symbol and the second symbol. The combined duration of the cyclic prefix in the first symbol and the second symbol is within one basic time unit of the duration of the cyclic prefix in the second symbol.

[0217] Example 66: A method according to Example 65, wherein the first set of subcarriers has a different subcarrier spacing than the second set of subcarriers.

[0218] Example 67: A method according to Example 65, wherein the leading edge of the first symbol is aligned with the leading edge of the third symbol in the time domain, and wherein the trailing edge of the second symbol is aligned with the trailing edge of the third symbol in the time domain.

[0219] Example 68: A method according to Example 65, wherein a combination of the total symbol duration of the first symbol and the second symbol is less than one basic time unit of the total symbol duration of the third symbol.

[0220] Example 69: The method according to Example 65 further includes: sending at least a fourth symbol and a fifth symbol on the first subcarrier set in the frame, the fourth symbol and the fifth symbol having the same useful symbol duration as the first symbol and the second symbol; and sending at least a sixth symbol on the second subcarrier set in the frame, the sixth symbol having the same useful symbol duration as the third symbol, but having a cyclic prefix duration different from that of the third symbol, wherein the combined duration of the cyclic prefixes of the fourth symbol and the fifth symbol is within one basic time unit of the duration of the cyclic prefix of the second symbol.

[0221] Example 70: A method according to Example 69, wherein the duration of the cyclic prefix in the fourth symbol is equal to the cyclic prefix in the fifth symbol.

[0222] Example 71: A method according to Example 69, wherein the duration of the cyclic prefix in the fourth symbol is half the duration of the cyclic prefix in the sixth symbol.

[0223] Example 72: An apparatus comprising: a processor; and a non-transitory computer-readable storage medium storing a program executed by the processor, the program comprising instructions for: sending at least a first symbol and a second symbol on a first subcarrier set in a frame, the first symbol and the second symbol being consecutive sequence numbers in the time domain, the first symbol and the second symbol having the same useful symbol duration and a different cyclic prefix duration; sending at least a third symbol on a second subcarrier set in a frame, the third symbol having a useful symbol duration different from the first symbol and the second symbol, wherein the combined duration of the cyclic prefix in the first symbol and the second symbol is within one basic time unit of the duration of the cyclic prefix in the second symbol.

[0224] Example 73: A computer program product, comprising a non-transitory computer-readable storage medium, the non-transitory computer-readable storage medium storing a program, the program comprising instructions, the instructions being used to: send at least a first symbol and a second symbol on a first set of subcarriers in a frame, the first symbol and the second symbol being symbols that are consecutive in the time domain, the first symbol and the second symbol having the same useful symbol duration and a different cyclic prefix duration; send at least a third symbol on a second set of subcarriers in a frame, the third symbol having a useful symbol duration that is different from the first symbol and the second symbol, wherein the combined duration of the cyclic prefixes in the first symbol and the second symbol is within one basic time unit of the duration of the cyclic prefix in the second symbol.

[0225] Example 74: A method performed by an apparatus in a wireless communication system, the method comprising: sending and receiving data using at least one of a first time / frequency resource set and a second time / frequency resource set; wherein the frequency spacing between subcarriers of an OFDM symbol carried by the first time / frequency resource set is different from the frequency spacing between subcarriers of an OFDM symbol carried by the second time / frequency resource set, and wherein the transmissions on the first time / frequency resource set and the second time / frequency resource set are subframe aligned; wherein when the first time / frequency resource set carries one or more downlink OFDM symbols, the downlink OFDM symbol carried by the first time / frequency resource set temporally overlaps with at least one of: a downlink OFDM symbol carried by the second time / frequency resource set and a guard period in the second time / frequency resource set; and wherein when the first time / frequency resource set carries one or more uplink OFDM symbols, the uplink OFDM symbol carried by the first time / frequency resource set temporally overlaps with at least one of: an uplink OFDM symbol carried by the second time / frequency resource set and a guard period in the second time / frequency resource set.

[0226] Example 75: A method according to Example 74, wherein for a specific duration: the first time / frequency resource set includes a first protection period inserted between a first downlink OFDM symbol and a first uplink OFDM symbol; and the second time / frequency resource set includes a second protection period inserted between a second downlink OFDM symbol and a second uplink OFDM symbol; wherein the first protection period and the second protection period start at different times but end at the same time.

[0227] Example 76: A method according to Example 74, wherein for a specific duration: the first time / frequency resource set carries uplink OFDM symbols and downlink OFDM symbols; the second time / frequency resource set carries only downlink OFDM symbols and includes one or more protection periods; and the uplink OFDM symbols carried by the first time / frequency resource set overlap in time with the protection period in the second time / frequency resource set.

[0228] Example 77: A method according to Example 76, wherein another uplink OFDM symbol carried by the first time / frequency resource set partially overlaps with a downlink OFDM symbol carried by the second time / frequency resource set.

[0229] Example 78: A method according to Example 74, wherein for a specific duration: the first time / frequency resource set carries uplink OFDM symbols and downlink OFDM symbols; the second time / frequency resource set carries only uplink OFDM symbols and includes one or more protection periods; and the downlink OFDM symbols carried by the first time / frequency resource set overlap in time with the protection period in the second time / frequency resource set.

[0230] Example 79: A method according to Example 74, wherein: the third time / frequency resource set has a subcarrier frequency spacing different from the subcarrier frequency spacing of the first time / frequency resource set and the second time / frequency resource set; the transmission on the third time / frequency resource set is subframe aligned with the transmission on the first time / frequency resource set and the second time / frequency resource set; when the first time / frequency resource set carries one or more downlink OFDM symbols, the downlink OFDM symbols carried by the first time / frequency resource set overlap in time with the downlink OFDM symbols carried by the third time / frequency resource set and at least one of the protection periods in the third time / frequency resource set; and when the first time / frequency resource set carries one or more uplink OFDM symbols, the uplink OFDM symbols carried by the first time / frequency resource set also overlap in time with the uplink OFDM symbols carried by the third time / frequency resource set and at least one of the protection periods in the third time / frequency resource set.

[0231] Example 80: A method according to Example 78, wherein the subcarrier frequency spacing of the first time / frequency resource set is 7.5kHz, the subcarrier frequency spacing of the second time / frequency resource set is 15kHz, and the subcarrier frequency spacing of the third time / frequency resource set is 30kHz.

[0232] Example 81: A method according to any one of Examples 74 to 80, wherein the apparatus is a base station or a mobile device.

[0233] Example 82: A method according to any one of Examples 74 to 81, wherein the subcarrier frequency spacing of one of the first time / frequency resource set and the second time / frequency resource set is 15kHz, and the subcarrier frequency spacing of the other of the first time / frequency resource set and the second time / frequency resource set is 30kHz.

[0234] Example 83: A device comprising: at least one antenna for sending and receiving data in a wireless communication system using at least one of a first time / frequency resource set and a second time / frequency resource set; wherein the frequency interval between subcarriers of OFDM symbols using the first time / frequency resource set is different from the frequency interval between subcarriers of OFDM symbols using the second time / frequency resource set, and wherein the transmissions on the first time / frequency resource set and the second time / frequency resource set are subframe aligned; wherein when the first time / frequency resource set carries one or more downlink OFDM symbols, the downlink OFDM symbols carried by the first time / frequency resource set overlap in time with at least one of the downlink OFDM symbols carried by the second time / frequency resource set and a protection period in the second time / frequency resource set; and wherein when the first time / frequency resource set carries one or more uplink OFDM symbols, the uplink OFDM symbols carried by the first time / frequency resource set overlap in time with at least one of: an uplink OFDM symbol carried by the second time / frequency resource set and a protection period in the second time / frequency resource set.

[0235] Example 84: A method performed by an apparatus in a wireless communication system, the method comprising: sending and receiving data using a time / frequency resource set, the time / frequency resource set comprising: a plurality of time durations, each time duration having a length t R , and each duration for sending or receiving is t R A single regular cyclic prefix (CP) OFDM symbol; a guard period, in which there is no data transmission, the guard period is inserted between the downlink transmission and the uplink transmission; wherein the duration of the guard period is t G ≥t L , where t L is equal to the duration of a single long CP OFDM symbol, and where t L >t R .

[0236] Example 85: The method of Example 84, wherein the duration of the protection period is t G = k × t L , where k is an integer and k ≥ 1.

[0237] Example 86: The method of Example 85, wherein the guard period is inserted for a duration of t R The downlink conventional CP OFDM symbol and duration is t R Between uplink conventional CP OFDM symbols.

[0238] Example 87: The method of Example 85, wherein immediately preceding the guard period there is a length t for transmitting a single long CP OFDM symbol L duration, and wherein immediately following the guard period there is a period of length t for transmitting a single conventional CP OFDM symbol R duration.

[0239] Example 88: The method of Example 84, wherein the guard period is inserted for a duration of t R The downlink conventional CP OFDM symbol and duration is t R The uplink conventional CP OFDM symbols are arranged between the uplink conventional CP OFDM symbols, and the duration of the guard period is t G = k × t R +t E , where k is an integer and k ≥ 0, and where t E is the duration of the extra CP between the long CP OFDM symbol and the normal CP OFDM symbol for the coexistence parameter set with the lowest subcarrier spacing.

[0240] Example 89: A method according to any one of Examples 84 to 87, wherein when the subcarrier spacing of the OFDM symbol is 7.5 kHz, t L =t R +1.04μs; when the subcarrier spacing of the OFDM symbol is 15kHz, t L =t R +0.52μs; when the subcarrier spacing of the OFDM symbol is 30kHz, t L =t R +0.26μs; and when the subcarrier spacing of the OFDM symbol is 60kHz, t L =t R +0.13μs.

[0241] Example 90: A method according to any one of Examples 84 to 89, wherein the apparatus is a base station or a mobile device.

[0242] Example 91: A method according to any one of Examples 84 to 90, wherein the time / frequency resource set is a first time / frequency resource set, wherein transmissions on the first time / frequency resource set are symbol aligned with transmissions on a second time / frequency resource set, and a first OFDM symbol in a subframe of the first time / frequency resource set is subframe aligned with a first OFDM symbol in a subframe of the second time / frequency resource set.

[0243] Example 92: An apparatus comprising: at least one antenna for transmitting and receiving data in a wireless communication system using a time / frequency resource set, the time / frequency resource set comprising: a plurality of time durations, each time duration having a length t R , and each duration for sending or receiving is t R A single regular cyclic prefix (CP) OFDM symbol; a guard period, in which there is no data transmission, the guard period is inserted between the downlink transmission and the uplink transmission; wherein the duration of the guard period is t G ≥t L , where t L is equal to the duration of a single long CP OFDM symbol, and where t L >t R .

[0244] Summarize

[0245] Although the present invention has been described with reference to specific features and embodiments of the features, various modifications and combinations may be made thereto without departing from the present invention. Therefore, the specification and the accompanying drawings are simply regarded as illustrations of some embodiments of the present invention, and are intended to cover some or all modifications, variations, combinations or equivalents falling within the scope of the present invention. Therefore, although the present invention and its advantages have been described in detail, various changes, substitutions and alterations may be made without departing from the present invention. In addition, the scope of the present application is not intended to be limited to the specific embodiments of the processes, machines, manufactures, material compositions, devices, methods and steps described in the specification. Those of ordinary skill in the art will readily understand from the disclosure of the present invention that processes, machines, manufactures, compositions, means, methods or steps currently existing or developed later that perform substantially the same functions as the corresponding embodiments described herein or achieve substantially the same results therewith may be used according to the present invention. Therefore, the appended claims are intended to include those processes, machines, manufactures, material compositions, devices, methods or steps within their scope.

[0246] In addition, any module, component, or device illustrated herein for executing instructions may include or be capable of accessing a non-transitory computer / processor readable storage medium for storing information or a medium for information storage, such as computer / processor readable instructions, data structures, program modules, and / or other data. A non-exhaustive list of examples of non-transitory computer / processor readable storage media includes magnetic cassettes, magnetic tape, disk storage or other magnetic storage devices, optical disks (e.g., compact disk read only memory (CD-ROM), digital video disks or digital versatile disks (DVD), Blu-ray Discs, and the like). TMor other optical storage), volatile and non-volatile, removable and non-removable media implemented in any method or technology, random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other storage technology. Any of these non-transitory computer / processor storage media may be part of the device or accessible or connectable to the device. Any application or module described herein may be implemented using computer / processor readable / executable instructions stored or otherwise held in a non-transitory computer / processor readable storage medium.

Claims

1. A communication method, characterized in that: The method comprises: Receive k consecutive time units with a first subcarrier spacing, a single time unit among the k consecutive time units has a duration t1, other time units among the k consecutive time units except the single time unit have a downlink time unit and an uplink time unit, and each of the other time units among the k consecutive time units except the single time unit has a duration t2, wherein t2<t1, and k is an integer greater than 1; the single time unit among the k consecutive time units is replaced by a first protection period, and the first protection period is inserted between the downlink time unit and the uplink time unit; Receive n consecutive time units with a second subcarrier spacing, n>k, the first subcarrier spacing is smaller than the second subcarrier spacing, a fourth time unit among the n consecutive time units has a duration t3, the number of fourth time units is an integer greater than 1, due to the proportional relationship between the first subcarrier spacing and the second subcarrier spacing, an integer number of fourth time units are adjacent to each other, located at the same position as the single time unit among the k consecutive time units, and are replaced by a second protection period, the other time units among the n consecutive time units except the fourth time unit have a downlink time unit and an uplink time unit and each of the other time units among the n consecutive time units except the fourth time unit has a duration t4, wherein t4<t3, n is an integer greater than 1; the second protection period is inserted between the downlink time unit and the uplink time unit.

2. The method according to claim 1, characterized in that The total duration of the k consecutive time units is 0.5 ms.

3. The method according to claim 1, characterized in that The total duration of the n consecutive time units is 0.5 ms.

4. The method according to any one of claims 1, characterized in that The k consecutive time units and the n consecutive time units are received simultaneously.

5. The method according to any one of claims 1, characterized in that Receiving the k consecutive time units with the first subcarrier spacing and receiving the n consecutive time units with the second subcarrier spacing includes: receiving the k consecutive time units with the first subcarrier spacing on a first subcarrier set and receiving the n consecutive time units with the second subcarrier spacing on a second subcarrier set.

6. The method according to claim 5, characterized in that The first subcarrier set and the second subcarrier set belong to different carriers.

7. The method according to claim 5, characterized in that The first subcarrier set and the second subcarrier set belong to the same carrier.

8. The method according to any one of claims 1 to 7, characterized in that The first subcarrier spacing is 15 kHz, and the second subcarrier spacing is 30 kHz.

9. The method according to any one of claims 1 to 7, characterized in that: The first subcarrier spacing is 30 kHz, and the second subcarrier spacing is 60 kHz.

10. The method according to any one of claims 1 to 7, characterized in that k=7 and n=14.

11. The method according to any one of claims 1 to 7, characterized in that: The cyclic prefix of the single time unit among the k consecutive time units is longer than the cyclic prefix of each of the other time units except the single time unit among the k consecutive time units; and A cyclic prefix of the fourth time unit among the n consecutive time units is longer than a cyclic prefix of each other time unit among the n consecutive time units except the fourth time unit.

12. The method according to any one of claims 1 to 7, characterized in that A rear edge of the single time unit among the k consecutive time units is aligned with a rear edge of a fourth time unit among the n consecutive time units.

13. The method according to any one of claims 1 to 7, characterized in that The second subcarrier spacing is an integer multiple of the first subcarrier spacing.

14. The method according to claim 13, characterized in that The integer multiple is a power of two.

15. The method according to any one of claims 1 to 7, characterized in that The first subcarrier spacing is 15 kHz×2i, where i is an integer and i≥0, and the second subcarrier spacing is 15 kHz×2j, where j is an integer and j>i.

16. The method according to any one of claims 1 to 7, characterized in that The method is executed by a network side device, or the method is executed by a user side device, or the method is executed by a processing system in a network side device, or the method is executed by a processing system in a user side device.

17. A communication device, characterized in that: The device comprises a memory and at least one processor, wherein the at least one processor is configured to execute instructions stored in the memory so that the device performs the method according to any one of claims 1 to 15.

18. A computer-readable storage medium having a program stored thereon, the program comprising instructions, characterized in that: When the instructions are executed, the computer is caused to perform the method according to any one of claims 1 to 15.

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