Then, 5G-NR is recommended to operate with a TDD DL/UL switching period of 5 ms with the pattern of “DDDDDDDSUU” and the DL/UL ratio of 8:2 to attain synchronization with LTE. β TDD can be easily computed from Equation 6 for the allowed LTE TDD frame configurations. Time Division Duplex (TDD) accomplishes this using different time slots for uplink and downlink signals over the same frequency. 2. 1 frame은 10 개의 subframe으로 구성되고. The frame 402 has two 5 ms half frames 404, and each of the half frames 404 includes five 1 ms subframes 406. The radio frame structure for LTE TDD. To know more on LTE TDD vs FDD, visit our page on LTE TDD Vs FDD modes and go through LTE frame structure in both of these modes. fType 2: TDD Frame Structure. EP3416330A1 EP18185302. 1. Instead, we can define the pattern in much more flexible way using several parameters as shown below. For TDD synchronicity and interference, the critical points are when switching between transmission and reception, as shown in Figure 2. One TDD frame is composed of T = 10subframes, and the time length of each subframe is 1millisecond [2]. 7 μs. simplified LTE TDD frame structure and sug-gested keeping only one optimized frame struc-ture for LTE TDD mode. A. Even under dynamic TDD configuration , the TDD configuration can only change every 10 ms ( one radio frame ) . In LTE TDD, we defined 7 predefined pattern for UL and DL allocation in a radio frame. 4G/LTE - RACH. 4. < LTE FDD Uplink Frame Structure >. The LTE Application framework supports the following (partially fixed) configurations: Bandwidth mode: 20 MHz (100 PRBs) Cyclic prefix configuration: Normal cyclic prefix; Frame Structure: Type 1—FDD; Type 2—TDD. g. SC-FDMA and LTE Uplink. The purpose of different frame structures: flexible, multiple uses. A TDD frame structure is shown in below figure. Figure 1 shows the frame structure for LTE TDD Figure 1: TDD frame structure The frame consists of two "half-frames" of equal length, with each half-frame consisting of either 10 slots or 8 slots. Root ZC sequence order for. PCFICH (Physical Control Format Indicator Channel) PHICH (Physical Hybrid ARQ (Automatic Repeat reQuest) Indicator Channel) PDCCH (Physical Downlink Control Channel) Available for PDSCH (Physical Downlink Shared Channel) TDD guard period in special subframe. Configuring a Downlink Signal Under TDD Frame Structure. PRACH Preamble Setup. • A radio frame has duration of 10 ms. FIG. The ME7873L LTE RF Conformance Test System supports the LTE frequency bands deployed worldwide, and users can choose the FDD/TDD test functions matching their test terminals. Signal Model Time Division Duplex (TDD) accomplishes this using different time slots for uplink and downlink signals over the same frequency. 811 subscribers. Frame Structure, Bandwidth Mode, CP Mode, and Physical Resource Grid. TDD stands for Time Division Duplex where as FDD stands for Frequency Division Duplex. TheThe LTE frame structure for the FDD and TDD schemes was discussed in Chapter 9. At least one of said second number of subframes is made to comprise at least three parts, as follows:. LTE provides flexibility of using existing and new frequency band as. Frame Structure Type 1. Type 2: used for the LTE TDD systems. 5G Waveforms, Frame Structure, and Numerology | 5G Explained. 4G/LTE - PHY Channel PSS (Primary Synchronization Channel). For FDD, whether downlink and uplink TDD. LTE Downlink Channel Estimation and Equalization. BRIEF DESCRIPTION OF THE DRAWINGS Various embodiments of the invention are disclosed in the following detailed description and the accompanying draw 1ngS. 10 ms radio frame, 1 ms sub frame. The slot is of 0. There are two types of LTE frame structures. LTE has radio frame of duration 10ms consisting of 10 subframes. 21). This ensures that both FDD LTE and TDD LTE are able to meet the high data throughput requirements placed upon them. 2. 0 LTE TDD Subframe Configuration Feature ISSUE 1. OEO116120 LTE eRAN3. 1; and Type 2, which is used in TDD and is the minor mode [24]. Single Ack/Nack corresponding to 1DLsub frame LTE DL Frame Structure in a Nutshell. Frame structure type 1 Figure 21. Two duplex schemes FDD and TDD are supported. We focus on the mandatory parts of the standard for both the BS and the MS, i. 1. e. The LTE frame is formed of 10 subframes (SF) of duration 1 ms each and sub-divided into 14 OFDM symbols. All. The downlink and uplink frame structure parameters are the same, except that the time-domain underlying symbols in the downlink are OFDM symbols, whereas in the uplink the underlying symbols are SC-FDMA symbols due to the use of different multiple access methods in. Instead, we can define the pattern in much more flexible way using several parameters as shown below. PDCCH occupies 1,2,3, or 4 OFDM symbols. Can schedule 1 DL and multiple UL sub-frame at a time. 1. FDD frame structure type is used. • A radio frame has duration of 10 ms. The TD-LTE frame structure is shown in Figure 1. 5 ms or 10 ms periodicity. 11 and Rel. Second, we present a detailed characterization of the Star-link downlink signal structure in the 10. 5 ms. channel coding. Frame structure type 1 is applicable to both full duplex and half duplex FDD. part 2 Figure 26. B. Here D-is downlink, S-for Sp e-cial sub frame and U - for Uplink. Figure€E. The invention discloses a method (500) for a cellular communications system (100), in which traffic is sent in frames (200), each frame comprising a first number of subframes (201-210), with a second number of said subframes being available for at least either uplink or downlink traffic. Each. I think this kind of subframe structure would clear up a lot of confusion. Frame Structure. This section describes the design and implementation of an OFDMA-TDD PHY compliant with the mobileWiMAX standard. Switching Points. Differences between LTE-FDD and LTE-TDD. 72 (=0. Part 2, Advanced topics in LTE 11:00 – 12:30 The LTE MIMO modes Codebook-based precoding Closed. 3rd frame is always used for Uplink transmissionLTE TDD Frame Structure ? FDD|| TDD क्या है I अगर प्रोटोकॉल टेस्टिंग की है तैयारी तो जरूर देखो. • The equipment requires to be switched between transmission and reception. The NG-RAN includes new generation LTE eNodeB (ng-eNB) and 5G NodeB (gNB), which are responsible for the radio functions, e. UE hence learns the frame structure in the subframe. 2. CMCC,CATT, etc. The concept would be similar to legacy LTE TDD Subframe configuration, but main differences from LTE TDD subframe configuration are. the amount of signaling overhead. InFrame Structure Understanding the 5G NR Physical Layer Waveform, Numerology and Frame Structure 21 – Frame: 10 ms – Subframe: Reference period of 1 ms – Slot (slot based scheduling) • 14 OFDM symbols • One possible scheduling unit - Slot aggregation allowed • Slot length scales with the subcarrier spacingLet us understand LTE FDD and TDD LTE versions with figures and band example below. TDD and FDD. Each frame is divided into ten equally sized subframes. Three different types of physical channels are defined for theThis site is for everything on 4G/LTE. 1, TDD frames of different cells are aligned in the time domain. For multiple access, LTE uses: For down link: OFDMA: Orthogonal Frequency Division Multiple Access. There are three wireless carriers in China nowadays supporting TDD-LTE and FDD-LTE services. Then, 5G-NR is recommended to operate with a TDD DL/UL switching period of 5 ms with the pattern of “DDDDDDDSUU” and the DL/UL ratio of 8:2 to attain synchronization with LTE. e. Figure 6. 1. frame [9]. The downlink and uplink frame structure parameters are the same, except that the time-domain underlying symbols in the downlink are OFDM symbols, whereas in the uplink the underlying symbols are SC-FDMA symbols due to the use of different multiple access methods in. TDD Frame Structure LTE’s frame structure ‘type 2’ supports Time Division Duplex (TDD) mode. The support for both TDD, half and full-duplex FDD is handled by two very similar frame structures: frame structure type 1 for half and full-duplex FDD and frame structure type 2 for TDD. FDD LTE uses a paired spectrum, while TDD LTE uses an unpaired spectrum. 2(a) illustrate the two types, respectively. 2 MHz for interworking with LCR TDD, but these were removed when the LTE TDD frame structure was aligned with the FDD frame structure rather than the TD-SCDMA frame structure from UMTS. – Frame structure type 2 (FS2): TDD. However, regardless of numerology the length of one radio frame and the length of one subfame is same. Flexible Bandwidth: 1. As a basic scheduling unit, each slot can be configured by the base station via physical layer signaling. The subcarrier spacing is f=15kHz LTE supports two radio frame structures Type 1, applicable to frequency division duplex FDD Type 2, applicable to time division duplex TDD 1 radio frame = 10ms 1 subframe= 1ms 1 slot = 0. However, employing TDD will lead to a long transmission latency due to the uplink/downlink transmission constraints. The structure of LTE TDD frame is defined by the Uplink/Downlink Configuration, that specifies which subframes are configured as downlink, which are uplink, and which are special subframes,. The example is shown for the case of 10 MHz bandwidth using. frame structure for OFDM systems . In TD-SCDMA a super-frame of 720 ms duration is made of 72 radio frames of 10 ms duration each. Frame Stracture. In TDD mode, the SF is either of type DL, UL or special (Spc). This new frame structure is designed to make LTE signal similar to WLAN burst. In LTE TDD, if a subframe (equivalent to a Slot in NR) is configured for DL or UL, all of the symbols within the subframe should be. LTE, TDD frame structure uses. 15, 2009. An operator can choose a specific TDD configuration depending on the service requirements; Frame always starts with a Downlink subframe, used for advertising the frame descriptor information i. In. Figure 3 shows the frame structure for LTE in FDD mode (Frame Structure Type 1). LTE FDD. Initially developed as 3. Frame Stracture. same time at different frequencies. I got all of the following examples using Sandesh Dhagle's Resource Grid. To introduce subslots into the TDD structure without impacting the overall subframe structure would mean limited gain, and to change the overall frame. When operating in TDD mode, we have to clearly define on exactly when to expect the transmission and when to expect the reception. This video looks at OFDM waveforms, and the different subcarrier spacings supported in 5G NR. 9A EP18185302A EP3416330A1 EP 3416330 A1 EP3416330 A1 EP 3416330A1 EP 18185302 A EP18185302 A EP 18185302A EP 3416330 A1 EP3416330 A1 EP 3416330A1 AuthorityIn another embodiment, the first radio frame and the second radio frame are two different frames belonging to the same downlink / uplink configuration period. Current frame structures consist of 8 timeslots in the downlink (DL) and 2 timeslots in the uplink (UL) which allows a maximum of 180 Mbit/s2 peak throughput under optimum conditions in the uplink (with 100MHz spectrum bandwidth, 2x2 UL MIMO and without UL prodevelopertutorial May 17, 2020. OFDMA and Downlink Frame Structure Details. The The LTE frame structure for the FDD and TDD schemes was discussed in Chapter 9. 1. Compared with the 3. Hierarchy of Frame Structure : Frame (Radio. . Hi All,There are lot of new member joined so i am providing the links of ORAN videos whi. As shown in Fig. FDD version is used where both uplink and downlink data rates are symmetrical. The following text shows the frame structure of each type. 2 LTE TDD In case of TDD operation, there is only one single carrierFig. One such specific consideration is for TDD operation where the existing TDD frame structure in LTE up to Release 14 was based on downlink subframes, uplink subframes and special subframes. In this example we will be simulating what happens when a mobile phone is turned on. When selecting one of the LTE Frame ConfigurationMethods and systems are provided for supporting co-existence of two radio access technologies (RATs), which include determining the frame structure of a first RAT, including the boundary of subframes, the DL:UL subframe ratio, and switching periodicity, selecting a frame offset and a DL:UL subframe ratio in a second RAT to minimize the number of. Frame: N+1) in the wimax frame structure. In the case of TDD operation (frame structure type 2, middle part of Figure 5. 10 ms radio frame, 1 ms sub frame. LTE standard has been published by 3GPP as an extension of UMTS (based on 3GPP standard) and 1xEV-DO (base on 3GPP2 standard) technologies. - CP Sequence TCP TSEQ Figure 3: Random access preamble format [2] 9. The WiMAX frame adopts a subframe ratio structure of 29:18, the LTE TDD frame adopts a subframe ratio structure of subframe configuration 1, and an UpPTS time slot and a last uplink symbol of a last uplink subframe which are in the LTE TDD frame. The TDD guard period must be long enough for the farthest NB of which the signal still could be seen. Length of one slot is fixed. The LTE-TDD frame structure can be adjusted to have either 5ms or 10ms DL-UL switch point periodically. There are two types of frame structures in LTE; type 1 used for FDD and type 2 for TDD, as shown in the diagrams above. The transmission timeline for the downlink and uplink may be partitioned into units of radio frames, and each radio frame may be partitioned into 10 subframes with indices of 0 through 9. An operator can choose a specific TDD configuration depending on the service requirements; Frame always starts with a Downlink subframe, used for advertising the frame descriptor information i. The TDD frame structure can be configured in seven different sub frame formats; however sub frames 0 and 5 and DwTS are reserved for downlink transmission. Methods and systems are provided for supporting co-existence of two radio access technologies (RATs), which include determining the frame structure of a first RAT, including the boundary of subframes, the DL:UL subframe ratio, and switching periodicity, selecting a frame offset and a DL:UL subframe ratio in a second RAT to minimize the number of. OFDM symbol duration reduces with increased SCS -> since the number of. 3 GHz TDD technology in [15] and. 89 Figure 6. HI all,Please go through video of LTE Frame Structure (FDD and TDD). codes in LTE). UMTS TDD. Additionally, NR supports transmission based on mini-slot (a fraction of a slot) as a minimum scheduling unit. LTE’s main advantages come from the following features:The manner of transmitting SRS in LTE TDD is mainly the same as that in LTE FDD. Frame structure in LTE-TDD systems. Choose a configuration with more “D”s in the frame means greater proportion of Downlink Data (normal for most Internet /ISP applications). In 5G/NR, we don't have any. The LTE architecture consists of LTE EUTRAN and LTE Evolved Packet Core (EPC). In addition, LTE air interface supports both frequency division duplexing (FDD) and time division duplexing (TDD). For the examples of TDD resource grids for each Subframe DL/UL Configuration and Special Subframe Configuration, see Frame Structure Frame Type 2 Overview section. Choose. These parameters are defined in 38. Can Schedule 1 DL and 1 UL subframe at a time. Signal Studio for LTE/LTE-Advanced FDD currently supports only FDD and frame structure type 1. The resulting capacity gain equals the “spectral efficiency gain x spectrum used”. At least one of said second number of subframes is made to comprise at least three parts, as follows:. Type 2: used for the LTE TDD systems. At least one of said second number of subframes is made to comprise at least. The downlink and uplink frame structure parameters are the same, except that the time-domain underlying symbols in the downlink are OFDM symbols, whereas in the uplink the underlying symbols are SC-FDMA symbols due to the use of different multiple access methods in. Downlink Uplink Frame TIME. 211 frame structure type 2 (DL / UL / SSF) Correct choice of Configuration value is essential when setting the UL/DL ratio for CableFree LTE networks using TDD bands. It is well understood in the industry that multiple overlapping LTE-TDD deployments in the same band can coexist if they align their frame boundaries and use the same TDD configuration. 3rd frame is always used for Uplink transmissionLTE-TDD Frame Structures. The LTE superframe supports the following configurations: Table 4: LTE TDD uplink-downlink configurations Uplink-downlink configuration. 1, TDD frames of different cells are aligned in the time domain. Physical Resource Block and Resource Element A Physical. Configuration of special subframe Figure 24. URLLC within a carrier should be supported , and TDD with flexible UL / DL ratio is desirable . FDD and TDD LTE networks have been deployed on all continents. 4) is applied to Time Division Duplex (TDD) mode maintaining only full duplex operation. There are six time units: frame, half-frame, subframe, slot. It consists of a 10 ms radio frame divided into 20 slots, numbered 0 to 19, each with a duration of 0. from publication: Robust Doubly-Differential Primary Synchronization Approach for 3GPP LTE Systems. We have investigated the suitable IO before designing the radar system. The target of TDD. 8. Based on GP in the special sub-frame of TDD LTE-A system, a novel positing scheme is proposed in this paper by adding navigation signal. frame structure optimization indicated higher. (Credit: 3GPP TS 38. The TDD guard period must be long enough for the farthest NB of which the signal still could be seen. In the following, only LTE TDD signals with. Introducing sTTI in LTE has conflicting design aspects with regards to the frame structure. Increasing frame configuration; Configuration: 3GPP release: Downlink to uplink switch point. In LTE base station is referred as eNodeB and mobile subscriber is referred as UE. This ingenious method enables full-duplex (simultaneous) communication over a half-duplex (serial-binary) link. Frame structure Type 3N builds on the 3GPP frame structure with the addition of the new nframe concept. FDD has a Type1 frame structure and TDD has a Type 2 frame structure. The frame can be dynamically configured to any one of the preset configurations shown, depending on the instantaneous data transmission requirement. NR frame structure supports TDD and FDD transmissions and operation in both licensed and unlicensed spectrum. Uplink-downlink configurations Figure 23. 1. This video then walks you through the concept of carriers and. LTE offers a flexible range of channel bandwidth (1. 5 ms. Using the latency model shown in Figure 11. 10 ms radio frame, 1 ms sub frame. 5 ms or 10 ms periodicity. Now the focus will be also on the physical channels structure, their processing in both FDD and TDD mode of LTE. In this paper, we study the frame structure design for low latency communications in 5G TDD systems. (FDD) or unpaired (TDD) spectrum allocation • Mobility – Optimized for 0~15km/h – Support with high performance for 15~20 km/h. in Figure 1. LTE Physical Layer 2 radio frames are supported: 1. Figure 1 shows frame structure type 1, which can be used in either full-duplex or half-duplex FDD mode. A method performed by a wireless device for determining a timing advance (TA) offset in a new radio (NR) network is described herein along with associated network devices and systems. The uplink enhancement technology used by NR TDD and NR FDD can significantly increase the uplink data rate. 1-2 see p. A diagram of the radio frame structure is shown in Figure 9, which includes information at the frame level down to the OFDM symbol level. See full list on rfmw. Interference with neighboring Base Stations. 5G frame structures provide a fixed overall structure for defining data block transmission timing. 21). This paper presents the LTE duplexing modes: LTE-TDD (Time Division Duplexing) and LTE-FDD (Frequency. frequency band (Band n78) to define common TDD frame structures at national level. But as we see more diverse types of subframe structure (FDD-frame structure Type1, TDD -frame structure Type 2, LAA - frame structure type 3), I see my confidence gets weaker. The method comprises the following steps: the downlink reference signals are transmitted by a base station in a downlink subframe in a TDD system with a category 2 frame structure and the downlink reference signals are transmitted by. 1 The NG-RAN. 9 PDSCH REs in1 radio frame and 2 Tx antennas, TDD mode 0. – Frame structure type 1 (FS1): FDD. LTE Frame Structure Figure 1 describes the LTE frame structure for TDD mode [4]. FDD is operated in the paired spectrum (see Sect. Each subframe has two slots. It consists of a 10 ms radio frame divided into 20 slots, numbered 0 to 19, each with a duration of 0. • A resource block (RB) spans 12 subcarriers over a slot duration of 0. In TDD mode, the SF is either of type DL, UL or special (Spc). LTE is designed primarily for full duplex operation in paired spectrum. Hence there are total 20 slots in a radio frame. 2 DSUDDDSUDD (10ms duration), where different special subframe “S” configurations are possible such 1EP2479919A1 EP12160504A EP12160504A EP2479919A1 EP 2479919 A1 EP2479919 A1 EP 2479919A1 EP 12160504 A EP12160504 A EP 12160504A EP 12160504 A EP12160504 A EP. PMP frame to this LTE frame, the downlink start has to align to the beginning of subframe 4, not subframe 0. 03255 us) in 36. LTE frame structures used for TDD 36. In case of co-site deployment, slot- and frame structures may be aligned to simplify cell search and inter. duplex operation with the time frequency structures. < PRACH Preamble Format >. Marriage of single carrier transmission and FDMA;NB-IoT-U introduces frame structure Type 3N. In frame structure Type 1, each 10 ms radio frame is divided into 10 equally sized subframes. Operating Bandwidths for LTE Devices 3. One subcarrier has bandwidth of 15 kHz. - available for PMCH (Physical Multicast Channel) LTE Resource Grid. Compared with IMT-Advanced (e. For TDD, a subframe is either allocated to downlink or uplink transmission. In addition, the ME7873L can be tailored to the required test environment, matching customers' RF TRX, performance, and RRM requirements, as well as. However, unlike LTE-U, LAA use a special physical layer frame structure called Frame Structure Type 3 which didn't exisit before. 2. This example shows how to create a frame containing the cell-specific reference signals (CellRS) in each subframe. The frame structure below ( Figure 1) is applicable to TDD. TDD LTE-A frame, presented in Figure 1, has been built on top of the LTE frame structure type 2 [8]. This site is for everything on 4G/LTE. Initial Cell Search and Cell Selection. The scheduling based on the SIB (System Information Blocks) transmission. . This avoids inter-network interference. Network and Protocol Architecture. Refer LTE stack >>. Few major differences in TDD Radio frame structure results in. DL Control Channel. The frame consists of two "half-frames" of equal . Each half-frame consists of five subframes of length . There are seven diferent standardised LTE frame structure configuration. Technical Overview of 3GPP LTE| Hyung G. You might have experience how much complicated (confusing) it become about HARQ process in LTE in TDD mode. At the initial phase of LTE develoyment, you haven't doubt on that every LTE subframe would carries CRS(Cell Sepecific Reference Signal) in it. The actual LTE (4G) is based on 3GPP Release 11. 5 ms. In 5G/NR, we don't have any predefined pattern. LTE-TDD frame structure. 0 Table 4. 8 PDSCH REs in1 radio frame and 1 Tx antenna, TDD mode 0. There are two types of LTE frame structure: Type 1: used for the LTE FDD mode systems. in Figure 1. For the normal mode, the first symbol has a cyclic prefix of length TCP = 160 ⋅ Ts ≈ 5. LTE TDD is designed to co-exist with 3GPP TD-SCDMA, and as a result, uses the same frequency bands and frame structure. International Search Report for PCT/CN2008/001840 dated Jan. FDD The uplink FDD frame contains only uplink user transmissions and is same length as the. LTE Frame structure. Essentially, when operating a 5G or 4G LTE network in a TDD environment, we not only need frequency and phase synchronization, but also frame and slot synchronization. 211. 7 μs. A method for use in a cellular communications system, in which system the traffic is sent in frames, each frame comprising a first number of subframes, with a second number of said subframes being available for at least either uplink or downlink traffic, according to which method at least one of said second number of subframes is made to. g. Number of. Difference is that in LTE TDD, a half- frame of length 5ms has both uplink sub-frame and downlink sub-frame, a number of uplink sub-frames and downlink sub-frames is configured by the. LTE also support both TDD and FDD, but unlike the single frame structure used in NR, LTE uses two different frame structures. Fig. This ingenious method enables full-duplex (simultaneous) communication over a half-duplex (serial-binary) link. It is. 3. efficiency and coverage because of the frame structure, and the nature of the spectrum unutilized for TDD being deployed in high bands. Furthermore, different frame structures, especially for TDD configurations, are not discussed even though NB-IoT is required to support TDD. The current version of the document focuses on Band 48 [11] LTE-TDD using Frame Structure 2 (FS2) [4][16] and limited support for n48 [18][19] NR-TDD deployment. cyclic prefix). UL and DL time slots, Downlink Pilot Timeslot (DwPTS) – downlink part of special subframe, Uplink Pilot Timeslot (UpPTS) – uplink part of special subframe, Guard Period (GP) The Special Subframe in LTE-TDD (DwPTS, GP, UpPTS)The main objective of the presented field measurement campaign was to confirm that the laboratory measurement results of LTE local network systems using 2. The table shown below is outlining key parameters of the 5G network's physical layer frame structure for different numerologies (denoted by μ). As a result of the differences in the radio frame structure between LTE TDD and LTE FDD, the resource elements are also configured differently. 5ms duration. 8 Mbit/s, which is an eight-fold increase. Basic Layer 1 Details of TDD. it means the start of the LTE frame is found and frequency. PSS and SSS frame structure In 3GPP LTE systems, downlink and uplink transmissions are organized into radio frames with 10ms duration. It enables very low latency, fast HARQ acknowledgments, dynamic TDD, coexistence with LTE and transmissions of variable length (for example, short duration for URLLC and long duration for enhanced MBB (eMBB)). Overview-TDD: Frame Structure Type 2 < TDD LTE Frame Structure > Followings are examples for various TDD UL/DL configurations. There are seven possible configurations for LTE TDD frame as shown below. Fig. Additional information on other system parameters is also listed in Table 2. Frame Structure Type 2: TDD. LTE Parameters and Downlink Modulation. Technical Overview of 3GPP LTE | Hyung G. Each subframe composed of 2 time slots. Main differences in LTE Frame Structure between the two modes are. The target figures for data throughput in the downlink is 1 Gbps for 4G LTE Advanced. Some parameters do not apply to the Basic LTE PRACH and Basic LTE-A PRACH. N TA,offset for a TDD uplink transmission is. The 10 ms frame comprises two half frames, each 5 ms long.