7 μs. length, w ith each half-frame consis ting of eithe r 10 . Choose a configuration with more “D”s in the frame means greater proportion of Downlink Data (normal for most Internet /ISP applications). PRACH Preamble Setup. The slot is of 0. LTE-TDD systems provide 7 different semi-static UL-DL configurations of an LTE frame to offer asymmetric DL-UL allocations (see Table II), hence providing DL-UL allocation ratios that vary from 4:6 to 9:1 (the number of DL-UL subframes) [12]. As a consequence, as the OFDM symbol duration is the. A method and system are provided for supporting co-existence of a first radio access technology (RAT) and a second radio access technology in adjacent channels, the boundary of subframes, downlink to uplink (DL: UL). 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. 8 Mbit/s, which is an eight-fold increase. 0 LTE TDD Subframe Configuration Feature ISSUE 1. UE hence learns the frame structure in the subframe. TDD LTE is much better in the allocation of traffic than FDD LTE. In other embodiments, the first and second radio frames are two different ones that fall within the same downlink/uplink configuration period. 03255 us) in 36. 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)). There are two types of LTE frame structure: Type 1: used for the LTE FDD mode systems. FDD frame structure type is used. 9 PDSCH REs in1 radio frame and 2 Tx antennas, TDD mode 0. Frame Structure, Bandwidth Mode, CP Mode, and Physical Resource Grid. Figure 1: TD D frame str ucture . 8. Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) Both paired and unpaired. 5 times higher compared to a classic LTE 4×4 configuration. This section describes the design and implementation of an OFDMA-TDD PHY compliant with the mobileWiMAX standard. 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. . channel coding. 10 ms radio frame, 1 ms sub frame. There are six time units: frame, half-frame, subframe, slot. 3. 2 μs. 211 V1. frequency band (Band n78) to define common TDD frame structures at national level. Figure 20. 1. The current version of the document focuses on Band 48 [11] LTE-TDD using Frame Structure 2 (FS2) The NR frame structure supports TDD and FDD transmissions and operation in both the licensed and the unlicensed spectrum. 11 – LTE-TDD PBCH measurement example. Myung 16 3GPP LTE. The radio frame is represented in the LTE Toolbox™ product by the use of a succession of 10 cell-wide settings structures with the NSubframe field set from 0 through 9 in each case. FDD is operated in the paired spectrum (see Sect. 12 – Example of VBW setting for LTE-FDDand LTE-TDD to avoid underestimation. 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. A. 1-2 see p. We have investigated the suitable IO before designing the radar system. 211 4 Frame structure). The HI all,Please go through video of LTE Frame Structure (FDD and TDD). Frame structure Type 3N builds on the 3GPP frame structure with the addition of the new nframe concept. 1, TDD frames of different cells are aligned in the time domain. 7 to 12. Can Schedule 1 DL and 1 UL subframe at a time. In TDD, the transmission is divided into time domain, means at one moment of time either downlink. approved DD Month YYYY. We will go through Mobile WiMAX OFDMA physical layer which. (Preamble format 4 is used only in TDD LTE. Frame Structure Type 2: TDD. NR frame structure supports TDD and FDD transmissions and operation in both licensed and unlicensed spectrum. Each. 3. There are seven possible configurations for LTE TDD frame as shown below. Increasing frame configuration; Configuration: 3GPP release: Downlink to uplink switch point. 7µs. The frame structure for the type 2 frames used on LTE TDD is somewhat different. A TDD includes a special subframe that has two pilot timeslots such as uplink and downlink that are separated from a GP (Guard. The TDD guard period must be long enough for the farthest NB of which the signal still could be seen. 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. The frame 402 has two 5 ms half frames 404, and each of the half frames 404 includes five 1 ms subframes 406. the amount of signaling overhead. com This page covers LTE Frame structure including subframe and slot structure. TS0 is always assigned as the downlink direction an conveys control messages such as the broadcast channel (BCH) while TS1 is always allocated as uplink. . 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. 1 and 10. As shown in the figure below, an LTE TDD frame is made of total 20 slots, each of 0. CN105993137A CN201580008676. 7 μs. An apparatus for a user equipment (UE) device, comprising baseband circuitry having a radio frequency (RF) interface configured to receive downlink (DL) signals and transmit uplink (UL) signals during a succession of long-term evolution (LTE)—time division duplex (TDD) radio frames, and one or more processors configured to: determine, based on a. Depending on configuration, they can concatenate multiple DL subframe and add only one UL control in the last subframe. Figure 1 shows frame structure type 1, which can be used in either full-duplex or half-duplex FDD mode. TDD frame structure. 5 GHz band, the uplink peak data rate increases by 18. The present invention provides systems, apparatuses, methods, and computer-readable media for a User Equipment (UE) device comprising one or more processors configured to determine, based on a DL signal in an LTE-TDD radio frame, that an eNB has evaluated that the radio frame is valid based on a Cat-2 Listen Before Talk (LBT) procedure; and in. Figure 1: LTE Generic Frame Structure [3] 2. In TDD, each slot can be flexibly configured into uplink and downlink symbols. UL Control Channel. Carrier aggregation is supported by both formats of LTE, namely the FDD and TDD variants. Type 1 Frame = A Type 1 Frame is used in the FDD mode. TD-LTE has a 10 ms TDD frame structure. Basic Layer 1 Details of TDD. Timing and Synchronization – Essential for 5G-NR TDD network successof the TDD configuration structure. For example, the public network has more downlinks, and the private network or private network has more uplinks. 5. 첫째로 Fig. DL Control Channel. URLLC within a carrier should be supported , and TDD with flexible UL / DL ratio is desirable . Download scientific diagram | LTE-TDD frame structure from publication: A Study on Channel Estimation Algorithm with Sounding Reference Signal for TDD Downlink Scheduling | Coping with the limited. 8. FDD LTE is ideal for symmetric traffic, while TDD LTE is ideal for asymmetric traffic. Coexistence between CBSDsThe NR frame structure supports TDD and FDD transmissions and operation in both the licensed and the unlicensed spectrum. – A compatible frame structure (including TDD DL/UL ratio and frame length) in order to avoid simultaneous UL/DL transmissions (guard periods may be. To set up a fixed reference channel (FRC), for an Advanced LTE TDD Uplink carrier, click the Wizard button Uplink Setup node to open the PRACH Wizard. Hence there is guard period between transmission and reception to avoid interference. 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. Further each radio frame is divided into two sub frames each of 5ms. · Sub-frame size= 1 ms. Configuration of special subframe Figure 24. Type 2: Used in LTE TDD. 참고로 규격은 3GPP의 TS36. This section only discusses how to. The concept would be similar to legacy LTE TDD Subframe configuration, but main differences from LTE TDD subframe configuration are. 4G/LTE - RACH. As shown in Figure 1, the total length of downlink pilot time slot (DwPTS), GP, and uplink pilot time slot (UpPTS) fields is equal to 1 ms duration. 3. It also explains OFDMA TDD frame which consists of PUSC, FUSC and AMC Zones in the downlink and PUSC/AMC zones in the Uplink. NR uses flexible subcarrier spacing derived from basic 15 KHz subcarrier spacing used in LTE. In addition, LTE air interface supports both frequency division duplexing (FDD) and time division duplexing (TDD). 8 PDSCH REs in1 radio frame and 1 Tx antenna, TDD mode 0. 2. Expected in the 2008 time frame, LTE is a 3GPP standard that provides for an uplink speed of up to 50 megabits per second (Mbps) and a downlink speed of up to 100 Mbps. 2. The following text shows the frame structure of each type. In Fig. Hence there are total 20 slots in a radio frame. 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. 4. when μ = 0. 1 provides an illustration of an LTE FDD and TDD frame structure as an example of an air interface with FDD and TDD modes. balance between resolution of channel quality estimation and. It describes LTE TDD frame structure and LTE FDD frame structure as per 3GPP standard. 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. UE hence learns the frame structure in the subframe. The useful symbol time is Tu = 2048 ⋅ Ts ≈ 66. Less. The LTE frame structure for the FDD and TDD schemes was discussed in Chapter 9. Frame Structure Type 1. . LTE supports two radio frame. One of the design principles of 5G NR has been the ability to coexist within the LTE physical layer structure to allow for sharing the existing 4G spectrum with new 5G devices. 2. LTE TDD frame 36. WO2015123203A1 - Method and apparatus for determining a flexible subframe type in a lte-tdd system - Google PatentsLTE Frame Structure based on Peak to Average Power Ratio (PAPR) analysis. TDD Mode UL/DL Configuration Frame Structure for L TE-Advanced In the figures giving the analysis, the case numbers (Case #1, #2, and so on) refer to the occurrence of RACH triggerDemodulating an LTE Signal in MATLAB with LTE System Toolbox. Two duplex schemes FDD and TDD are supported. The LTE physical layer supports two types of frame structures as types 1 and 2. LTE TDD Frame Configuration These first three groups of settings apply to all basic carriers. LTE: Key Features. , 3:1 DL/UL ratio with 5 ms DL/UL switching period. 5G NR TDD self-contained slot structure in action Three examples showcasing faster TDD switching for low latency DL reference signals (DL DMRS) & UL Reference + Sounding (UL DSMR, SRS) not showed for simplicity. Second, we present a detailed characterization of the Star-link downlink signal structure in the 10. 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. When selecting one of the LTE Frame ConfigurationThere are total 10 subframes in a frame. It is a TDD type of frame structure which is a natural choice since ETSI band 54 and FCC band 902–928 MHz are both unpaired bands. 3rd frame is always used for Uplink transmission Time Division Duplex (TDD) accomplishes this using different time slots for uplink and downlink signals over the same frequency. 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 ULType 1: FDD : Frequency Division Duplex. 4 shows a frame structure 400 for a Time Division Duplex Long Term Evolution (LTE TDD) carrier. Slot Structure. This video then walks you through the concept of carriers and. LTE standard has been published by 3GPP as an extension of UMTS (based on 3GPP standard) and 1xEV-DO (base on 3GPP2 standard) technologies. TDD stands for Time Division Duplex where as FDD stands for Frequency Division Duplex. Downlink and uplink transmissions are organized in the form of radio frames with 10 ms duration (Fig. Recommendation No 2: A migration roadmap of all LTE and WiMAX legacy systems in the relevant bands should be defined 5 Synchronisation at a national level 6 Recommendation No 3: All networks should use the same frame structure at a national level 6 Synchronisation at an international level 8 The frame structures for LTE differ between the Time Division Duplex, TDD and the Frequency Division Duplex, FDD modes as there are different requirements on segregating the transmitted data. Type 1: Used in LTE FDD. The target of TDD. 5G NR frame Structure. • A radio frame has duration of 10 ms. . This applies for the currently-transmitting Starlink satellites (versions 0. This example shows how to create a frame containing the cell-specific reference signals (CellRS) in each subframe. There are two types of LTE frame structure: 1. 2. Although the time -domain structure is, in most respects, the same for FDD and TDD, there are some differences, most notably the presence of a special sub frame in the case of TDD. 5ms, each slot is composed of 7 symbols (normal cyclic prefix), therefore a resource block of 12 subcarriers by 7 symbols occupies one slot. Technical Overview of 3GPP LTE | Hyung G. As a result, the uplink power level due to SC-FDMA also need to be increased by 2~3dB to compensate for the extra noise due to more spreading. 0, and 1. 7 μs. FDD LTE has come from a 3G network migration path, while TDD LTE came from TD-SCDMA. MHz spectrum, we have to use this 20 MHz bandwidth for both DL and UL. LTE frame structures used for TDD 36. 3GPP defines two types of frames based. This is shown in figure after uplink subframe(of frame: N) and before next downlink subframe (i. This applies for the currently-transmitting Starlink satellites (versions 0. But in NR, the number of slots varies according to the numerology. frame [9]. 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. Time Division Duplex Wireless is a fundamental technology for 5G deployments around the world. The Fading parameters are available for Advanced LTE and Advanced LTE-A TDD. 2009-1-27 2 Outline • LTE requirement. Number of OFDM symbols per slot, slots per frame, and slots per subframe for normal cyclic prefix. Uplink and downlink configurations are used to create subframes (0 to 6). Downlink Uplink Frame. 6 bps/Hz for LTE-A 2×2 to 7 bps/Hz for 5G NR 64TRX. e. 1 Downlink physical layer The LTE downlink PHY is specified for bandwidths from 1. This page is moved soon to Guard Period in TDD Bands makes them highly inefficient if used in lower frequency configurationThe LTE TDD frame structure is Type 2. The frame structure is divided into three types: FDD, TDD, FDD and TDD. k) that the frame structures given in Annex 1, Frame A and Frame B can be implemented for NR(New Radio) systems; l) that the Frame B2 given in Annex 1 is compatible with the LTE-TDD frame structure configuration n o. LTE-TDD frame structure. Under the flexible frame structure, each radio frame consists of a plurality of slots, and each slot within a radio frame has a flexible slot type. Use the LTE Toolbox™ to create a frame worth of data, pass it through a fading channel and perform channel estimation and equalization. The LTE-TDD frame structure can be adjusted to have either 5ms or 10ms DL-UL switch point periodically. LTE-FDD와 LTE-TDD의 기술적인 차이는 통신 계층으로 보면 Layer 1 (Physical layer)만 다르다. • A radio frame has duration of 10 ms. ECC Recommendation (20)03. In 5G/NR, we don't have any. Figure 1: TD-LTE Frame Structures Each one millisecond downlink subframe contains blocks of data (“resource. For FDD, whether downlink and uplinkThe Third Generation Partnership Project (3GPP) has been studying dynamic allocation of sub-frames to uplink or downlink in Time Division Duplex (TDD), since the Long Term Evolution (LTE) Rel. Radio frames and subframes are of fixed lengths. The remaining six symbols have a cyclic prefix of length TCP = 144 ⋅ Ts ≈ 4. In LTE, DL and UL transmissions are organized into radio frames of 10 ms each. The slot is of 0. It is defined as 1/(15000 x 2048) seconds (=0. Signal Studio for LTE/LTE-Advanced FDD currently supports only FDD and frame structure type 1. 5 ms. This video has been taken from our LTE Air Inte. OFDMA and Downlink Frame Structure Details. Figure 7A illustrates a CA frame structure 700 for a TDD-TDD carrier aggregated PUSCH-less cell arrangement for data transmission between a UE 115 and BS 105 according to some. The table shown below is outlining key parameters of the 5G network's physical layer frame structure for different numerologies (denoted by μ). Frame structure type 2(for 5ms switch-point periodicity) Figure 22. May 6, 2021 On-Demand Demo See a Celona 5G LAN in action and learn the basics Get Access This episode of Field Journal we’ll go deep into the TDD-LTE frame structure in the CBRS spectrum band, and touch on. Fig. Figure 3 shows the frame structure for LTE in FDD mode (Frame Structure Type 1). There are seven possible configurations for LTE TDD frame as shown below. 1 shows an example of such TDD configuration structure in LTE with T= 10 [2]. Unique Feature of 5G Subframe comparing to LTE : Multiple. Frame Structure Type 2. When operating in TDD mode, we have to clearly define on exactly when to expect the transmission and when to expect the reception. A TDD frame structure similar to that in [39, Figure ] is considered for all the BSs and UEs with synchronous operation. You’ll also learn about the impact of different subcarrier spacings on slots and subframes. Part 1, LTE Basics 9:30 – 10:30 Introduction to LTE FDD/TDD frame structures and reference signals Physical channels, logical channels PHY signal processing architecture H-ARQ processing, H-ARQ timing UE categories. These are; - Type 1 FDD (Frequency Division Duplexing) - Type 2 TDD (Time Division Duplexing) Type 1: It is designed for frequency division duplex, and is valid for both half duplex, and full. For multiple access, LTE uses: For down link: OFDMA: Orthogonal Frequency Division Multiple Access. Single Ack/Nack corresponding to 1DLsub frameFrequency Division Duplex (FDD) and Time Division Duplex (TDD) are the prevailing duplexing scheme in LTE that provides deployable tractability according to spectrum assignation. Root ZC sequence order for format 0-3. In this paper, we study the frame structure design for low latency communications in 5G TDD. Instead, we can define the pattern in much more flexible way using several parameters as shown below. Choose. Carrier Aggregation in TDD. Instead, we can define the pattern in much more flexible way using several parameters as shown below. 6 symbols. 11 and Rel. • The figure-3 depicts UMTS TDD frame structure. 2. 2 LTE TDD In case of TDD operation, there is only one single carrierFig. LTE PHY layer overview. 9G (Pre-4G) cellular technology Now sold as 4G. As known, LTE traffic is divided into two parts: an uplink and a downlink transmission. tdd UL/DL Common Configuration (tdd-UL-DL-configurationCommon) in Detail . MHz spectrum, we have to use this 20 MHz bandwidth for both DL and UL. 5 milliseconds. 3GPP has defined 7 frame structures for LTE-TDD. Type 2: used for the LTE TDD systems. Introducing sTTI in LTE has conflicting design aspects with regards to the frame structure. SC-FDMA and LTE Uplink. LTE TDD frame structure is shown . 2 LTE Frame Structure The frame structure is dependent on the duplex scheme applied in the spectrum. In 5G/NR, we don't have any predefined pattern. PSS and SSS frame structure In 3GPP LTE systems, downlink and uplink transmissions are organized into radio frames with 10ms duration. According to this, the SRS Status on each subframe become. 2 Mbit/s to 1. The target of TDD. OFDMA Downlink. You’ll also learn about the impact of different subcarrier spacings on slots and subframes. Under the existing LTE TDD frame structure , which subframe can be UL or DL is fixed within a radio frame . . International Search Report for PCT/CN2008/001840 dated Jan. g. LTE is designed primarily for full duplex operation in paired spectrum. However, regardless of numerology the length of one radio frame and the length of one subfame is same. 7 to 12. 9, 1. There are three types of Frame Structure : Type 1 for FDD, Type 2 for TDD, Type 3 for LAA. The type 1 structure (Fig. The screen shot below shows the parameter choices for a DL-SCH n channel. 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)). The Spc SF is placed between. LTE TDD frame structure is shown below. OneAdvisor Realtime Spectrum – LTE-FDD LTE-TDD Frame Structure LTE-TDD Structure LTE-TDD transmission is done in 10ms frames containing 10 sub-frames of 1ms and 20 slots of 0. Network and Protocol Architecture. 2. Myung 17 Frame Structure • Two radio frame structures defined. 25 MHz to 20 MHz. Figure 3 shows the frame structure for LTE in FDD mode (Frame Structure Type 1). 72 (=0. In TD-SCDMA a super-frame of 720 ms duration is made of 72 radio frames of 10 ms duration each. Conformance Test Setup. A. 4. e. Frame Structure Candidates . 3GPP Release 8, 2009. Type 1: FDD : Frequency Division Duplex. 2 μs. In this paper, we analyze the performance of SC-FDMA and OFDMA in LTE Frame Structure based on Peak to Average Power Ratio (PAPR) analysis. When operating in TDD mode, we have to clearly define on exactly when to expect the transmission and when to expect the reception. Initial Cell Search and Cell Selection. A TDD frame structure is shown in below figure. · Sub-frame size= 1 ms. Three different types of physical channels are defined for the#5G #NR #TDD #ResourceAllocation #LTE #TDD #Resource #Allocation #DownLink #UpLink #SpecialSubframes#SymbolLevelResourceAllocation#SubFrameLevelResounceAlloc. There are two types of LTE frame structure: Type 1: used for the LTE FDD mode systems. With this shift, the sequence of subframes in the LTE frame becomes D, D, S, U, U, which is the same structure of the Cambium PMP frame (downlink, turnaround time, uplink). Furthermore, it provides the mobile community’s views on the preferred frame structure for initial 5G launches in 3. Switching Points. Channel Mapping and UE Categories. 0 Table 4. 3rd frame is always used for Uplink transmissionLTE-TDD Frame Structures. Signal Studio for LTE/LTE-Advanced FDD currently supports only FDD and frame structure type 1. Choose a configuration with more “D”s in the frame means greater proportion of Downlink Data (normal for most Internet /ISP applications) Frame Structure. 1. 2 μs. LTE carrier aggregation basics. NB-IoT-U introduces frame structure Type 3N. if we chose subframe configuration 7(Frame structure type 1), T_SFC become 5 and Delta_SFC become {0,1}. All networks operating within the 3. 7 Furthermore, unlike LTE where the uplink-downlink allocation does not change over time, 8 the TDD operation for NR is designed with dynamic TDD as a key technology component. cyclic prefix). 10 such subframes form one radio frame. Each. Comparison against the corresponding LTE. e. LTE (telecommunication) In telecommunications, long-term evolution ( LTE) is a standard for wireless broadband communication for mobile devices and data terminals, based on the GSM / EDGE and UMTS / HSPA standards. In 4G LTE networks, both FDD and TDD, the transmissions are sent in radio frames of 10 milliseconds. There are three wireless carriers in China nowadays supporting TDD-LTE and FDD-LTE services. 2 DSUDDDSUDD (10ms duration), where different special subframe “S” configurations are possible such 1 The LTE frame is formed of 10 subframes (SF) of duration 1 ms each and sub-divided into 14 OFDM symbols. Figures 1 and 2 show the frame structures referenced in Table 1 . Very Basic understanding of Frame , subframe , slots and. 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,. 8. 03255) us. For TDD synchronicity and interference, the critical points are when switching between transmission and reception, as shown in Figure 2. Choose a configuration with more “D”s in the frame means greater proportion of Downlink Data (normal for most Internet /ISP applications) OneAdvisor Realtime Spectrum – LTE-FDD LTE-TDD Frame Structure LTE-TDD Structure LTE-TDD transmission is done in 10ms frames containing 10 sub-frames of 1ms and 20 slots of 0. Signal ModelTime Division Duplex (TDD) accomplishes this using different time slots for uplink and downlink signals over the same frequency. 2. 4. β TDD can be easily computed from Equation 6 for the allowed LTE TDD frame configurations. e. • In UMTS TDD, both uplink and downlink shares same frequency band at the same time period. What is claimed is: 1. This episode of Field Journal we’ll go deep into the TDD-LTE frame structure in the CBRS spectrum band, and touch on the different 4G LTE deployment methods that are used in different environments. China adopted frame configuration DDDSUDDSUU (5ms) to support long PRACH formats and South Korea adopted. The default parameters for national TDD synchronization should be defined before awarding the spectrum. The invention discloses a method for a cellular communications system, in which 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. LTE Protocol Stack. LTE Introduction. Numerology – Subcarrier Spacing. It is a TDD type of frame structure which is a natural choice since ETSI band 54 and FCC band 902–928 MHz are both unpaired bands. MCCH modification period, repetition period radio frame offset, subframe allocation;. Let us explain how it works, and which factors need to be considered. Cyclic Prefix at beginning, remaining part is real symbol data. The radio frame is represented in the LTE Toolbox™ product by the use of a succession of 10 cell-wide settings structures with the NSubframe field set from 0 through 9 in each case. In Extended CP, number of symbols within a slot is decreased. 2. For the normal mode, the first symbol has a cyclic prefix of length TCP = 160 ⋅ Ts ≈ 5. · Each Radio frame consists two half frames. Figure 6. Each frame is divided into ten equally sized subframes. The useful symbol time is Tu = 2048 ⋅ Ts ≈ 66. Double-click or use the drop-down menu to set the subframe allocation for MBSFN within the radio frame allocation period defined by the two parameters: Radio Frame Allocation Period and Radio Frame Allocation Offset. Introduce LTE TDD – FDD Carrier Aggregation support (aggregation of carriers with different frame structures) including either TDD or FDD as PCell(*) satisfying the following conditions: UEs supporting FDD and TDD carrier aggregation operation shall be able to access both legacy FDD and legacy TDD single mode carriers;LAA . 5 ms repetition period. Frame Stracture. 10 mili second radio frame consists of Downlink subframe, Uplink subframe and Special subframe. 1- Providing UE with Cell-Specific Slot format Configuration (tdd-UL-DL-ConfigurationCommon) 2- Providing UE with dedicated Slot format configuration (tdd-UL-DL-ConfigurationDedicated) 1- : RRC : tdd-UL-DL-ConfigurationCommon. There are three types of Frame Structure : Type 1 for FDD, Type 2 for TDD, Type 3 for LAA. 21). 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. UL Control Channel. Can Schedule 1 DL and 1 UL subframe at a time.