BRIEF DESCRIPTION OF THE DRAWINGS Various embodiments of the invention are disclosed in the following detailed description and the accompanying draw 1ngS. 5 ms. 3GPP defined seven frame structures for LTE-TDD, where only a limited number of configurations allocate more transmission time to the DL than the UL and have a 5 ms periodicity, which is necessary for compatibility with NR for quicker response. UE hence learns the frame structure in the subframe. Frame Structure Type 1. simplified LTE TDD frame structure and sug-gested keeping only one optimized frame struc-ture for LTE TDD mode. 5G frame structures provide a fixed overall structure for defining data block transmission timing. · Sub-frame size= 1 ms. IWSON / VTC2015 Summary In LTE-TDD, the amount. The duration of each subframe is 1 ms. These are Type 1 when FDD is used and Type 2 when TDD is used. < TDD UL/DLConfiguration 0, Special Subframe Config 0 > < TDD UL/DLConfiguration 1, Special Subframe Config 0 >Strategies and Implementations to Support Multiple Wireless Protocols with a Single RF Front-end A Thesis Presented by Mohamed Abdelrahman MohamedIn many countries, n78 (3500 MHz), or commonly referred to as the 3. Nzc is determined by the following table. 1 shows an example of such TDD configuration structure in LTE with T= 10 [2]. 00In the TDD frame structure of a wireless communication system such as LTE, a single frequency block is shared in the time domain between UL and DL transmission. Each frame is then divided into ten subframes of 1-millisecond duration. Switching Points. 7 μs. In TDD (Time division duplex) technique we are using, same frequency or frame for both DL and UL but at a different time. Hence there are total 20 slots in a radio frame. This avoids inter-network interference. The useful symbol time is Tu = 2048 ⋅ Ts ≈ 66. 2 TDD Configurations The goal of the CBRS Alliance is to allow flexible use of CBRS band if coexistence of multiple deployments is preserved. Unique Feature of 5G Subframe comparing to LTE : Multiple. cyclic prefix). In an FDD scheme, all ten subframes within a radio frame contain either downlink or uplink subframes depending on the link. e. In 5G/NR, we don't have any predefined pattern. Frame structure Type 3N builds on the 3GPP frame structure with the addition of the new nframe concept. 10 subframes (= 20 slots) are fit into 10 ms in LTE while various number of slots depending on Numerology are fit into 10 ms in 5G NR. This new frame structure is designed to make LTE signal similar to WLAN burst. LTE video tutorials covering OFDM, frame structure, Cell mapping, random access procedure. 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. In LTE TDD, we defined 7 predefined pattern for UL and DL allocation in a radio frame. em. 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. . 5 ms. 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). Figure 8: LTE-TDD frame structure Each subframe has a 1ms length, and can be used in the 3 following modes: "D" (downlink), "U" (uplink) and "S" (switching point). Probably what I do as the first step is to describe each part of the map in a verbal form Overview-TDD : Frame Structure Type 2 < TDD LTE Frame Structure > 5/26 4/19/22, 2:11 PM ShareTechnote Followings are. For TDD synchronicity and interference, the critical points are when switching between transmission and reception, as shown in Figure 2. 즉, 1개의 Radio Frame은 10개의 Subframe!! 여기서 1ms의 Subframe 길이가 TTI (Transmission. LTE의 Frame 구조는 FDD와 TDD로 나누어 규격에 정리되어 있다. Type 1: FDD : Frequency Division Duplex. Marriage of single carrier transmission and FDMA;NB-IoT-U introduces frame structure Type 3N. 10 ms radio frame, 1 ms sub frame. However the system structure of LTE TDD is different from of that in LTE FDD. Very Basic understanding of Frame , subframe , slots and OFDM symbols1. Type 1 Frame = A Type 1 Frame is used in the FDD mode. Uplink and downlink configurations are used to create subframes (0 to 6). Signal Studio for LTE/LTE-Advanced FDD currently supports only FDD and frame structure type 1. This paper presents the LTE duplexing modes: LTE-TDD (Time Division Duplexing) and LTE-FDD (Frequency. Flexible Bandwidth: 1. FDD LTE has come from a 3G network migration path, while TDD LTE came from TD-SCDMA. OFDMA and Downlink Frame Structure Details. There are 20 slots in 10 ms long FDD whereas a 10 ms long TDD is divided into two subframes of length 5 ms each. 89 Figure 6. 4 LTE mobile device availability summary 4. However, employing TDD will lead to a long transmission latency due to the uplink/downlink transmission constraints. When selecting one of the LTE Frame ConfigurationThere are total 10 subframes in a frame. 2. But in NR, the number of slots varies according to the numerology. 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. A. Carrier aggregation is supported by both formats of LTE, namely the FDD and TDD variants. simplified LTE TDD frame structure and sug-gested keeping only one optimized frame struc-ture for LTE TDD mode. NR uses flexible subcarrier spacing derived from basic 15 KHz subcarrier spacing used in LTE. Frame Stracture. For the normal mode, the first symbol has a cyclic prefix of length TCP = 160 ⋅ Ts ≈ 5. 211 V1. Hi All,There are lot of new member joined so i am providing the links of ORAN videos whi. In LTE TDD, we defined 7 predefined pattern for UL and DL allocation in a radio frame. 5 GHz 5G band, or C-band 5G, is the most commonly tested and deployed 5G frequency. Determining a frame structure of the first RAT comprising a subframe rate, and switching periodicity, at least in part to a corresponding. 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. 3. and slot 12 (Subframe 6) in TDD. Each frame is divided into ten equally sized subframes. LTE-TDD and NR-TDD CBSDs, GAA channelization and SAS-CBSD protocol extensions. Operating Bandwidths for LTE Devices 3. 4. 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. This section describes the design and implementation of an OFDMA-TDD PHY compliant with the mobileWiMAX standard. 1. The numerology in 5G is used to define these parameters, and includes the su LTE TDD frame 36. Frame structure type 2 is applicable to TDD. It is valid for both half duplex, and full duplex FDD modes. Part 2, Advanced topics in LTE 11:00 – 12:30 The LTE MIMO modes Codebook-based precoding Closed. , 3:1 DL/UL ratio with 5 ms DL/UL switching period. This release is the second stage of the LTE-Advanced realization. LTE, TDD frame structure uses. 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,. UMTS TDD. 7 to 12. This article describes OFDMA basics, OFDMA frame structure,OFDMA symbol, OFDMA Physical layer as per IEEE 802. 5 ms. UE hence learns the frame structure in the subframe. SC-FDMA and LTE Uplink. Figure 1: LTE Generic Frame Structure [3] 2. Switching Points. At least one of said second number of subframes is made to comprise at least. In LTE, DL and UL transmissions are organized into radio frames of 10 ms each. – A compatible frame structure (including TDD DL/UL ratio and frame length) in order to avoid simultaneous UL/DL transmissions (guard periods may be. In. LTE TDD Frame Configuration These first three groups of settings apply to all basic carriers. Other limitations, such as pseudo-congestion and lack. In this paper, we study the frame structure design for low latency communications in 5G TDD systems. 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. Uplink-downlink configurations Figure 23. In 5G/NR, we don't have any predefined pattern. Time Division Duplex (TDD) accomplishes this using different time slots for uplink and downlink signals over the same frequency. As a result, the achievable capacity gain from M-MIMO antennas is approximately 2. Downlink and uplink transmissions are organized in the form of radio frames with 10 ms duration (Fig. MHz spectrum, we have to use this 20 MHz bandwidth for both DL and UL. 1 TDD—Time-Division DuplexFIG. 가장 큰 차이점은 프레임 구조와 HARQ이다. 2(a) illustrate the two types, respectively. 211 4 Frame structure). know, one sample (Ts) is 1/30. Frame Structure and Crossed Slots LTE-TDD frame consists of 10 sub-frames of 1 ms each. · Each Radio frame consists two half frames. subframe is transmitted or uplink. Switching Points . Two types of frames are defined for LTE: Type 1, which is used in FDD and is the dominant mode of operation as shown in Fig. • A resource block (RB) spans 12 subcarriers over a slot duration of 0. 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. 5ms, each slot is composed of 7 symbols (normal cyclic prefix), therefore a resource block of 12 subcarriers by 7 symbols occupies one slot. 5G TDD. given in Annex 1 is compatible with the LTE-TDD frame structure configuration no. 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. 10 ms radio frame, 1 ms sub frame. 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. The target figures for data throughput in the downlink is 1 Gbps for 4G LTE Advanced. LTE FDD. Here. Frame Structure Type 1. Type 2: Used in LTE TDD. UL Control Channel. I think this kind of subframe structure would clear up a lot of confusion. 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. duplex operation with the time frequency structures. As a consequence, as the OFDM symbol duration is the. Subframe is of fixed duration (i. g. 3. 3. LTE Frame Structure. The HI all,Please go through video of LTE Frame Structure (FDD and TDD). Finally, each subframe is split into two timeslots, each with a duration of 0. 7K views 2 years ago. 0 as follows : TDD-UL-DL-ConfigCommon ::= SEQUENCE04/02/2023 10 Types of Frame Structure in LTE: • Types of Frame structure in LTE: 3GPP defines two types of frames based on the duplexing scheme used. What is claimed is: 1. Configuring a Downlink Signal Under TDD Frame Structure. 0 LTE TDD Subframe Configuration Feature ISSUE 1. 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. 1. This site is for everything on 4G/LTE. Moreover, each subframe is further divided into two equally sized time slots, that is, each slot is 0. However, with static LTE-TDD, it is difficult to fulfill fast traffic adaptation, leading to the underutilization of base station resources. TDD uplink-downlink configuration: 5Figure 9 shows the LTE TDD frame structure: Figure 5 - LTE TDD Frame Structure (for 5 ms switch-point periodicity). 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. 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. In Frame 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 spacing Let us understand LTE FDD and TDD LTE versions with figures and band example below. Figure€E. Channel Mapping and UE Categories. In each subframe, there are two switching. frequency band (Band n78) to define common TDD frame structures at national level. LTE TDD Frame Configuration These first three groups of settings apply to all basic carriers. OEO116120 LTE eRAN3. When operating in TDD mode, we have to clearly define on exactly when to expect the transmission and when to expect the reception. 4. FIG. 7. To contrast, WiMAX operates in half duplex in unpaired spectrum, where information is transmitted in one direction at a time. Type 2: used for the LTE TDD…Although the latency constraint of 5G cannot be supported using the 1 ms TTI of LTE, it is insightful to take a look at the LTE TDD. We have investigated the suitable IO before designing the radar system. In TDD spectrum, for small/isolated cells it is possible to use dynamic TDD to adapt to traffic variations, while for large over-the-rooftop cells, Frame structure. tdd UL/DL Common Configuration (tdd-UL-DL-configurationCommon) in Detail . Many different bands: 700/1500/1700/ 2100 /2600 MHz . Frame Structure • Two radio frame structures defined. Downlink Uplink Frame. 3 TDD LTE Growth in the market 3. 5 ms); one slot consists of seven OFDM symbols. from below figure you can see for μ = 0 (highlighted row) Number of OFDM symbols in one slot = 14. 8. 10 mili second radio frame consists of Downlink subframe, Uplink subframe and Special subframe. In LTE TDD, there are 7 predefined patterns for UL and DL allocation. This applies for the currently-transmitting Starlink satellites (versions 0. 4G/LTE - MBSFN. TDD have a special sub frame (1,6) when downlink-to. Lte Frame Structure :TDD and FDD. Frame Structure Type1. The radio frame of 10 ms are transmitted continuously as per TDD topology one after the other. 00 - View presentation slides online. These parameters are defined in 38. Special Subframe Design for Optimized TDDsteps required to estimate synchronization structures that are likely unique to Starlink. 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. The LTE physical layer supports two types of frame structures as types 1 and 2. One sub frame is composed of 7 normal time slots used for downlink/uplink and 3 special time slots. Single Ack/Nack corresponding to 1DLsub frame LTE DL Frame Structure in a Nutshell. There has been long long discussions on frame structure both in academia and in 3GPP and now we have pretty clear agreements on what a NR(5G) radio frame would look like. 위의 그림이 FDD에 활용되는 Type1의 Frame 구조다. Figure 1 show s the frame structure fo r LTE TDD . Apart from some smaller differences in the frame structure and mapping of some physical signals, the overall physical layer processing (e. The target of TDD. (for FDD and TDD) and DCI Formats 2B/2C for TDD alone. PRACH Preamble Setup. lets take few example to understand frame structure in more details . Now the question comes, who decides the sequence of these subframes. In the TDD duplexing mode, a single bandwidth is shared between uplink and downlink, with the sharing being performed by. 2. In the case of TDD operation (frame structure type 2, middle part of Figure 5. 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. the amount of signaling overhead. FDD sTTI: New features in Rel. LTE: Key Features. • A radio frame has duration of 10 ms. < LTE FDD Uplink Frame Structure >. 1, 2007, pp. 2. 12 – Example of VBW setting for LTE-FDDand LTE-TDD to avoid underestimation. In TDD, the transmission is divided into time domain, means at one moment of time either downlink. 2 TDD Configurations The goal of the CBRS Alliance is to allow flexible use of CBRS band if coexistence of multiple deployments is preserved. This video then walks you through the concept of carriers and. PDCCH occupies 1,2,3, or 4 OFDM symbols. TDD frame structure. The 5G NR frame structure is defined by the 3GPP and here we present details of the NR Frame Structure that is specified in 3GPP specification (38. 2. 1 LTE Physical Layer. (Preamble format 4 is used only in TDD LTE. part 1 Figure 25. Subframes 0 and 5 contain synchronization signal and broadcast information necessary for a UE to perform synchronization and obtain relevant system information. 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. 36. 3rd frame is always used for Uplink transmissionLTE-TDD Frame Structures. 7 to 12. Each radio frame will have a total of ten subframes, each with two time slots. 3. However, regardless of numerology the length of one radio frame and the length of one subfame is same. steps required to estimate synchronization structures that are likely unique to Starlink. In the N7625C Signal Studio software, click a different channel to view that channel's parameter choices. Technical Overview of 3GPP LTE | Hyung G. Let me illustrate New Radio frame structures with multiple SCS below. So, it is very important to understand the slot structure and other details about slot-based scheduling etc. In LTE, a subframe is used as a minimum scheduling unit in time-domain while in NR, a slot is used as a dynamic scheduling unit. 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. Increasing frame configuration; Configuration: 3GPP release: Downlink to uplink switch point. 3 GHz TDD technology in [15] and. Each subframe has two slots. You’ll also learn about the impact of different subcarrier spacings on slots and subframes. 5), but will likely also apply forI made this quick video presentation to explain the difference between TDD and FDD Radio Frame. 8. β TDD can be easily computed from Equation 6 for the allowed LTE TDD frame configurations. 211 frame structure type 2 (DL / UL / SSF) Filter. 1, TDD frames of different cells are aligned in the time domain. But anyway good thing to me was that the most important factors in uplink slot is same as the one in the downlink. Downlink Uplink Frame. Figure 3 shows the frame structure for LTE in FDD mode (Frame Structure Type 1). There are three different kinds of units specified for this frame structure, illustrated in Figure 6. The special sub frame is used to provide the necessary guard time for downlink-uplink switching shown in Table 1. There are seven possible configurations for LTE TDD frame as shown below. 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 version is used where both uplink and downlink data rates are symmetrical. Fig. One way to avoid cross-link interference is to ensure that all base stations are either transmitting simultaneously or receiving simultaneously. One TDD frame is composed of í µí± = 10 subframes, and the time length of each subframe is 1 millisecond. LTE TDD is designed to co-exist with 3GPP TD-SCDMA, and as a result, uses the same frequency bands and frame structure. Three different types of physical channels are defined for the#5G #NR #TDD #ResourceAllocation #LTE #TDD #Resource #Allocation #DownLink #UpLink #SpecialSubframes#SymbolLevelResourceAllocation#SubFrameLevelResounceAlloc. 15 include slot and subslot configurations from Fig. Whereas further optimizations can be made for Frequency Division Duplexing (FDD) systems, the combination of sTTI and Time Division Duplexing (TDD) has limits. LTE Downlink Channel Estimation and Equalization. Signal Model Time Division Duplex (TDD) accomplishes this using different time slots for uplink and downlink signals over the same frequency. 9, 1. Figure 1. Frame Structure Candidates . Type 2: used for the LTE TDD systems. in Figure 1. 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. In LTE base station is referred as eNodeB and mobile subscriber is referred as UE. 2. UE hence learns the frame structure in the subframe. Let us explain how it works, and which factors need to be considered. Each subframe has two slots. We propose a frame structure design. This ensures that both FDD LTE and TDD LTE are able to meet the high data throughput requirements placed upon them. Additionally, NR supports transmission based on mini-slot (a fraction of a slot) as a minimum scheduling unit. The same signals. Root ZC sequence order for format 0-3. 5 ms or 10 ms periodicity. Uplink users transmit subframes, random-access requests (PRACH) and SRS during the UpPTS section of the special subframe. OFDM symbol duration reduces with increased SCS -> since the number of. Type 1: Used in LTE FDD Type 2: Used in LTE TDD The following text shows the frame structure of each type. 2. Signal ModelTime Division Duplex (TDD) accomplishes this using different time slots for uplink and downlink signals over the same frequency. Figures 1 and 2 show the frame structures referenced in Table 1 . Application. 2. TBS Index Advanced LTE TDD Carrier–DownlinkLTE-Advanced Physical Layer Overview. Subcarrier (SC)In LTE, the parameter N TA,offset is fixed, based on the FDD or TDD mode. 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. While FDD makes use of separate bands to transmit uplink and downlink data, TDD uses time slots on the same frequency for both uplink and downlink. PSS and SSS frame structure In 3GPP LTE systems, downlink and uplink transmissions are organized into radio frames with 10ms duration. 8. Slot Structure. Can Schedule 1 DL and 1 UL subframe at a time. 12 to enable features such as aggregation of carriers between time-division duplex (TDD) and frequency-division duplex (FDD) frame structures. TDD frame structure can thus be configured into 7 different formats of 1ms-subframes. Even under dynamic TDD configuration , the TDD configuration can only change every 10 ms ( one radio frame ) . 6 Conclusion. As a basic scheduling unit, each slot can be configured by the base station via physical layer signaling. 5 ms. Therefore, the accuracy. 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. The uplink edge rate increases from 0. Time division duplex (TDD) plays an important role in 5G systems because it employs an unpaired spectrum and offers channel reciprocity. Method for transmitting signals in uplink direction in a 3G mobile radio communication system, wherein - time- frequency resources for data transmission are structured in physical resource blocks - PRBs, - a time division duplex - TDD - frame structure comprising frames, each comprising several time slots, is provided for transmitting signals in uplink. 5ms, each slot is composed of 7 symbols (normal cyclic prefix), therefore a resource block of 12 subcarriers by 7 symbols occupies one slot. TDD systems has led to a few additional physical layer features exclusive to TDD mode [7]. LTE supports two radio frame structures: Type 1, applicable to the FDD duplex scheme and Type 2, applicable to the TDD duplex scheme. Choose. Frame Structure, Bandwidth Mode, CP Mode, and Physical Resource Grid. · Radio frame size= 10 ms. In LTE TDD, we defined 7 predefined pattern for UL and DL allocation in a radio frame. 5 ms 1 radio frame = 10 subframes = 20 slots. com This page covers LTE Frame structure including subframe and slot structure. Frame structure type 2(for 5ms switch-point periodicity) Figure 22. A. Frame structure type 1 Figure 21. TDD LTE is much better in the allocation of traffic than FDD LTE. 03255) us. Further enhancements followed in Rel. 1. Figures 10. Type 1 LTE Frame Structure. In a number of countries, there are legacy LTE TDD or WiMAX networks in the 3. 3GPP LTE Frame Structure 2, Applicable to TDD. As shown in Figure 3(a) , in the simultaneous operation of an LTE-U within a WiFi coverage area, the DL LTE-U radio link experiences interference from other LTE-U DL and WiFi UL transmissions. 1 section 2 lines 1-5, p. References. Each half-frame consists of five subframes of length . NB-IoT-U introduces frame structure Type 3N. Each frame is divided into ten equally sized subframes. Fig. . We focus on the mandatory parts of the standard for both the BS and the MS, i. 2 DSUDDDSUDD (10 ms duration), where different special. In LTE, we don't need any specific terminology to indicate the subcarrier spacing since there is only one subcarrier spacing, but in NR there are several different types of subcarrier spacing . 7 μs. Root ZC sequence order for. The LTE superframe supports the following configurations: Table 4: LTE TDD uplink-downlink configurations Uplink-downlink configuration. Radio frames and subframes are of fixed lengths. In TD-SCDMA a super-frame of 720 ms duration is made of 72 radio frames of 10 ms duration each. 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.