Timing advance sharetechnote. This corresponds to LTE subframe duration.

Timing advance sharetechnote Especially in frequency domain, you have so many resource blocks you can use (100 Resource Blocks in case of 20 Mhz Bandwidth As you see in the following figures, for Rel 8,9,10 there is no special tag for each component carrier, meaning that even in Carrier Aggregation single Timing Advanced value apply to all the component carriers. PRACH is used as timing reference for uplink during UE’s initial access, radio link failure, during Handover etc…The eNodeB sends Timing advance command in Random Access Response (RAR). The T3410 timer sets a deadline for the network to respond to the Attach Request. 10 0101 . PDSCH - Time Domain Allocation (DCI - PDSCH Timing) : K0 Following is the illustration showing the Time Domain resource allocation for PDSCH based on 38. I am trying to consolidate possible timelines proposed by various sources in this note This timing advance ensures that signals from the UE arrive at the base station synchronized with the base station's receive window, taking into account the round-trip delay. 1. Overview: UE Attach & RACH See Power Control page for the details. Once the UE is in connected mode, the eNodeB keep estimating Timing Advance and sends Timing Advance ntn-NeighCellConfigList-r17 Timing Adjustments: Introduces K_mac as a scheduling offset for aligning downlink and uplink frame timings. Mar 25, 2024 · Throughout a handover procedure, as the UE needs to initialized the timing advance for the new cell After a loss of timing synchronization with the gNB if the UE needs to received or forward data From recovery of a beam failure, if changes in the downlink propagation make the UE unable to received the current downlink beam. To be honest, the number of steps would look differently depending on how to split the whole procedure into smaller steps. Key elements of NTN include satellites (transparent or regenerative) that serve as critical intermediaries for transmitting and managing data. 2. Addressing delay spread in satellite communications involves incorporating advanced equalization and timing correction techniques that are robust enough to handle the variations, thereby aligning with 3GPP standards that aim for high-quality, clear communication. Frequency Information: Additional spectrum emission parameters. iii) Construct the resource grid from the received signal and the detected timing from step ii) Physical Layer Problem Example - Timing Error Most of wireless communication (practically every wireless communication that I know) works in very strictly synchronized timing between transmitter and reciever. In UMTS case, it is true that only RRC These formats are characterized by longer sequence lengths, providing better performance in terms of timing advance measurement and detection reliability in challenging conditions: 0, 1, 2, 3: The long sequence formats are designed to support scenarios with significant delay spreads and provide reliable performance over greater distances. One type is the one being transmitted periodically like NTN What is it ? Why NTN ? Challenges Tech Requirements Spectrum Architecture RACH Timing Advance RRC (NR) RRC (LTE) RRC (NB IoT) Call Flow (NB IoT) See Power Control page for the details. 214 - 5. Image Source : Sharetechnote NOTE : This feature is supported from the release 2021-12-17 RRC parameters for 5G NTN highlights the intricate configuration elements necessary for supporting advanced NTN functionalities in the 5G ecosystem. Simply put, Timing Advance is a special command (notification) from eNB to UE that enable UE to adjust its uplink transmission as shown May 16, 2021 · LTE: Timing Advance MAC CEThe eNodeB estimates the initial Timing Advance from PRACH sent by the UE. After repeating these open-look-close so many times, I decided to put all those terms in a single page for quick search. This kind of UL adjustment applies to PUSCH, PUCCH and SRS. NOTE 1 : Regarding the details of Timing Advance File, refer to Timing Advance Page NOTE 2 : 'Msg3 PUSCH time resource allocation' (K2 for msg3) would refer to pusch-ConfigCommon->pusch-TimeDomainAllocationList in RrcReconfiguration (in case of NSA) or in SIB1 (in case of SA). It showcases various AI workloads classified by their control loop timing: long timescales for tasks like prioritizing first responders, medium timescales for admission control and bandwidth prediction, and real-time processes for beamforming and scheduling. g, a smartphone or IoT sensor) using the network’s capabilities. 1-1: Uplink-downlink timing relation ? < 38. You will see this gets longer as new release comes out (Refer to LTE-Advanced MAC for the snapshot of the evolution ) MAC CE for LTE Advanced With the introduction of LTE Advanced, MAC CE has been extended a little bit further to meet the operations in LTE Advanced. Timing Advance Challenges Impact: The dynamic nature of satellite orbits and their extensive coverage areas introduce complexities in accurately calculating and adjusting timing advance for user equipment (UE). This capability is essential for a variety of cutting-edge 5G MIB / SIB in Detail Overall functionality and structure of MIB / SIB of NR is almost same as LTE, but there is one major differeces between NR and LTE. 5G/NR - MAC CE MAC CE (MAC Control Element) The purpose and function of NR MAC CE is almost same as LTE MAC CE. It means you need to do a lot of study on lower layer process to fully understand the details of this higher layer process and parameters that will be explained in this The variations among A1, A2, and A3 mainly address different levels of delay spread and timing advance requirements. The TAInfo-r17 provides details for timing advance, accounting for the large distances inherent in NTN communication. 0. So I suggest you to read LTE Timing Advance as well if you are not familiar with the concept. The UE monitors the radio environment and executes the handover at the optimal moment, without waiting for a new command. These parameters, defined within the 3GPP technical specifications, encompass essential elements such as NTN-specific configurations, reference locations, timing adjustments, and ephemeris information to facilitate satellite and high-altitude Positioning technology in cellular networks is the art and science of determining a device’s location (e. 133 v1. Timing Advance Timing Units TRS (Tracking Reference Signal) Type 0 PDCCH Common Search Space/RMSI-PDCCH-Config Type 1 PDCCH Common Search Space Type 2 PDCCH Common Search Space Type 3 PDCCH Common Search Space Two Step RACH (2 step RACH) UAC (Unified Access Control) UCI (Uplink Control Information) UDM UE Assistance Information UE Capability UE ID See Power Control page for the details. The uplink timing control based on the timing advance command is applied to PUSCH, PUCCH, and SRS in 5G NR. This offset at the UE is necessary to ensure that the downlink and uplink subframes are synchronised at the eNodeB. These parameters collectively compensate for round-trip delays and allow sufficient processing time for the UE between DL reception and UL transmission. Also, most See Power Control page for the details. : Additions in The eNB sends a Random Access Response (RAR), including timing advance information, uplink grant, and a temporary C-RNTI for the UE. 4G/LTE [+] Quick Reference Quick Picture Basic Procedure Troubleshoot Tips Frame Structure Downlink Uplink Reference Signal Low Layer Procedures DCI HARQ PHY Processing MIMO MIMO/CA (Big Pict. It would be good to have a few fundamental timing units that are frequently used in various part of physical 5G/NR - Uplink Transmission Timing Uplink Transmission Timing < 38. T3410: This timer is started when the UE (User Equipment) sends an Attach Request to the network. . It would be good to have a few fundamental timing units that are frequently used in various part of physical NTN Common Configuration: Settings specific to NTN, including timing advance reporting and t318. May 22, 2025 · IntroductionThe Random Access CHannel (RACH) procedure is the gateway to the 5G Standalone (SA) network. 4 for details NOTE 1 : Regarding the details of Timing Advance File, refer to Timing Advance Page NOTE 2 : 'Msg3 PUSCH time resource allocation' (K2 for msg3) would refer to pusch-ConfigCommon->pusch-TimeDomainAllocationList in RrcReconfiguration (in case of NSA) or in SIB1 (in case of SA). If multiple UEs transmitted the same preamble, they all receive this response. This timing synchronization requirement tend to get more and more strict as you go with higher end communication technology like LTE. 0110 1 . And when you think of Carrier Aggregation, the first question you may ask would be "If a UE is getting data from multiple carriers, how can it report ACK/NACK ?" With this question in mind,you may easily guess that we may need some additional way to handle this 4G/LTE - Timing Advance Timing Advance Timing Advance is a MAC CE that is used to control Uplink signal transmission timing. . See Power Control page for the details. Timing advance is a negative offset, at the UE, between the start of a received downlink subframe and a transmitted uplink subframe. It has grown from basic methods relying on proximity to a single tower to advanced systems that harness multiple signals, precise timing, and even artificial intelligence. Slot Decoding Timing Advance UE Capability Information (Useful for radio stack troubleshoot) 2G : GSM/GPRS Dictionary Band/ARFCN/Frequency Map Band Indicator Cell Channel Description Channel Mapping - GSM Channel Mapping - GPRS CS (Coding Scheme) - GPRS Frame Structure MCS (Modulation Coding Scheme) - EGPRS (EDGE) Protocol Stack : Overview 5G/NR - MAC CE Timing Advance The concept and functionality of NR Timing Advance is same as the LTE Timing Advance. g, sub carrier spacing, OFDM symbol length) varies in 5G/NR, you would see many physical layer parameters are specified by equations and variables instead of specific constants values. = T2 (TBF): 13 [TBF_Starting_Time: 26455] . In 5G SA, the initial attach procedure is launched through a contention-based RACH, triggered when a UE powers on or reselects a cell in RRC_IDLE. Refer to MAC in LTE Advanced page for the details. (2) Timing Control : Timing Advance This is the mechanism by which eNB adjust UE transmission power by observing the arrival time of PRACH signal or PUSCH and sending proper adjustment command. Timing Advance is a MAC CE that is used to control Uplink signal transmission timing. g, Idle mode DRX, Connected Mode DRX, BSR Report period etc) are configured within this max timiing value. 5G/NR - Physical Layer Timing Unit Physical Layer Timing Unit Since many physical layer things (e. 2G/GSM GPRS Packet Setup This page will show you some example of GPRS sessions for user traffics. com This page describes the 5G NR Uplink Timing Control Procedure based on the timing advance provided by the gNB to the UE. However, in NR there are two different types of SIBs. NTNs are revolutionizing the way we [Sharetechnote] does it mean that UE should start transmitting PUCCH at (the start symbol time of PUCCH - switching time) as well ? [Sakshama] yes true. 4G/LTE - Timing Advance Timing Advance Timing Advance is a MAC CE that is used to control Uplink signal transmission timing. 5G/NR - 2Step RACH 2 Step RACH As the term implies 2 Step RACH indicates a type of RACH procedure that are complete in 2 steps. Positioning technology in cellular networks is the art and science of determining a device’s location (e. Network (eNodeB in this case) keep measuring the time difference between PUSCH/PUCCH/SRS reception and the subframe time and can send a 'Timing Advance' command to UE to change the PUSCH/PUCCH transmission to make it better aligned with the subframe timing at the network Timing Advance is a MAC CE that is used to control Uplink signal transmission timing. Incorrect timing advance can lead to collisions between uplink transmissions from different UEs, or misalignment with the satellite's reception window, hindering successful communication. ) Precoding Fading Power Control PUCCH Protocols RACH SIB PAGING MAC RLC PDCP Full Stack [+] Basic Call Idle Mode Multi Cell UE Capability Conformance LTE RF/PHY RF Measurement LTE TDD Overview LTE IoT Most of timing related parameters (e. B1, B2, B3, B4: Optimized for medium to large cell sizes, these formats offer a balance between coverage and capacity. It's dynamic because the allocation between LTE and 5G can be done with a granularity of 1ms. Feb 24, 2024 · Dynamic Spectrum Sharing (DSS) is a feature introduced in 5G so that both LTE/4G and 5G systems can share the same spectrum. Only one training sequence is defined for this burst. This normal burst is used by TCH, SDCCH, SACCH, FACCH, BCCH and PCH. The exact timing of xPUSCH transmission is adjusted by Timing Advance value contained in RAR. When we say 'communication between UE and Network', we normally think about only signaling message (RRC or NAS message). NTN What is NTN ? NTN stands for Non-Terrestrial Networks, a concept in telecommunications that refers to communication networks that use non-terrestrial assets, such as satellites, high-altitude platforms, or drones, to provide connectivity. Any specific 3GPP statement (like the statement you made before) ? 5G/NR - MAC CE MAC CE (MAC Control Element) The purpose and function of NR MAC CE is almost same as LTE MAC CE. = TA_Valid: the timing advance value is valid . g, eDRX The variations among A1, A2, and A3 mainly address different levels of delay spread and timing advance requirements. NTN Common Configuration: Settings specific to NTN, including timing advance reporting and t318. Transmission Mode : Example 1 > Transmission Mode changes while driving in live network LTE Timing Advance - Example 1 > Timing Advance in a Live Network (in the field) RLC Factors on LTE throughput : Example 1 > PHY throughput and RLC Throughput in a drive test 5G/NR - Physical Layer Timing Unit Physical Layer Timing Unit Since many physical layer things (e. Network (eNodeB in this case) keep measuring the time difference between PUSCH/PUCCH/SRS reception and the subframe time and can send a 'Timing Advance' command to UE to change the PUSCH/PUCCH transmission to make it better aligned with the subframe timing at the network MAC CE - Timing Advance As you see in the following figures, for Rel 8,9,10 there is no special tag for each component carrier, meaning that even in Carrier Aggregation single Timing Advanced value apply to all the component carriers. Synchronization and Timing Accuracy Precise synchronization and timing accuracy between user equipment and the network are foundational requirements for efficient uplink transmission, especially in advanced scenarios involving MIMO, multi-user scheduling, or coordinated multi-point reception. I would not show all the radio signaling process for registration and initial attach for GPRS. NTNs are part of the broader effort to extend network coverage beyond the limitations of terrestrial infrastructure. It means that this message is carried by xCCCH SDU. Network (eNodeB in this case) keep measuring the time difference between PUSCH/PUCCH/SRS reception and the subframe time and can send a 'Timing Advance' command to UE to change the PUSCH/PUCCH transmission to make it better aligned with the subframe timing at The exact timing of xPUSCH transmission is adjusted by Timing Advance value contained in RAR. [Sharetechnote] Thank you. I think following illustration gives us pretty good idea of the evolution path. May 16, 2021 · Timing Advance is a MAC CE that is used to control Uplink signal transmission timing. OFDM is sensitive to timing discrepancies, which can cause inter-symbol interference. Timing Advance Timing Units TRS (Tracking Reference Signal) Type 0 PDCCH Common Search Space/RMSI-PDCCH-Config Type 1 PDCCH Common Search Space Type 2 PDCCH Common Search Space Type 3 PDCCH Common Search Space Two Step RACH (2 step RACH) UAC (Unified Access Control) UCI (Uplink Control Information) UDM UE Assistance Information UE Capability UE ID NOTE 1 : Regarding the details of Timing Advance File, refer to Timing Advance Page NOTE 2 : 'Msg3 PUSCH time resource allocation' (K2 for msg3) would refer to pusch-ConfigCommon->pusch-TimeDomainAllocationList in RrcReconfiguration (in case of NSA) or in SIB1 (in case of SA). 0110 = Protocol discriminator: Radio Resources Management messages (0x06) 0000 . 5G/NR - Acronyms There are so many Acronyms in 3GPP (probably in all other technologies) and these acronyms are defined in many different documents. 5G/NR - Synchronization Synchronization I think the most steps in any wireless system (especially high end wireless system like Cellular communication system) is Synchronization. 3. Timing Advance is a MAC CE that is used to control Uplink signal transmission timing. Simply put, Timing Advance is a special command (notification) from eNB to UE that enable UE to adjust its uplink transmission as shown below. Network (eNodeB in this case) keep measuring the time difference between PUSCH/PUCCH/SRS reception and the subframe time and can send a 'Timing Advance' command to UE to change the PUSCH/PUCCH transmission to make it better aligned with the subframe timing at the network NTN Common Configuration: Settings specific to NTN, including timing advance reporting and t318. Also, most 4G/LTE - Protocol Stack Full Stack Now that we covered each layer of LTE protocol stack, it is time to combine all these layers to a complete protocol stack. 5G/NR - tdd UL/DL Dedicated Configuration This configuration is to configure for TDD UL/DL pattern for dedicated UE (i. Jun 30, 2025 · Timing Advance (TA) is a critical concept in 4G Long-Term Evolution (LTE) and 5G New Radio (NR) systems, ensuring synchronized uplink transmissions from User Equipment (UE) to the base station (eNodeB in 4G, gNodeB in 5G). L. 4G/LTE - DCI DCI When you study the physical frame structure of LTE, you may be impressed by flexibility (meaning complexity in other way) of all the possible ways of resource allocation. The eNB sends a Random Access Response (RAR), including timing advance information, uplink grant, and a temporary C-RNTI for the UE. Any specific 3GPP statement (like the statement you made before) ? The exact timing of xPUSCH transmission is adjusted by Timing Advance value contained in RAR. Timing advance (TA) is used to control the uplink transmission timing of individual UE. NTN Requirement The technical requirements for Non-Terrestrial Networks (NTNs) are critical to ensuring their seamless integration and efficient operation alongside terrestrial communication systems. However, in terms of troubleshooting this step would be one of the trickest part. TAInfo-r17 n-TimingAdvanceOffset TDD LTE : SR/DCI 0 Timing TDD LTE : DCI 0/PUSCH Timing TDD LTE : System Information Variation Test Loopback Mode Test/Verification : Test Methodology TFT (Traffic Flow Template) Timer (RRC) Timer (EPS Mobile Management - UE Side) Timer (EPS Mobile Management - Network Side) Timer & Constant and RRC/NAS Message Timing Advance Throughput Explanation of the 5G NR uplink timing control procedure, timing advance, and related messages for synchronization between UE and gNB. Overall Procedure Why 2 step RACH ? Overview on Configuration RRC Parameters for Timing Advance Timing Units TRS (Tracking Reference Signal) Type 0 PDCCH Common Search Space/RMSI-PDCCH-Config Type 1 PDCCH Common Search Space Type 2 PDCCH Common Search Space Type 3 PDCCH Common Search Space Two Step RACH (2 step RACH) UAC (Unified Access Control) UCI (Uplink Control Information) UDM UE Assistance Information UE Capability UE ID Packet Timing Advance Control Channel /Uplink : Transmit Random Access Burst to allow estimation of the timing advance DL PTCCH/D Packet Timing Advance Control Channel /Downlink : Transmit Timing Advance updates UL MPRACH Used during the initial counting procedure for MBMS DL PNCH Notifying PtM Packet Transfer DL CPPCH Compact PPCH UL CPRACH This timing advance ensures that signals from the UE arrive at the base station synchronized with the base station's receive window, taking into account the round-trip delay. : Additions in R99: Not Present L . Overall process and Configuration of 2 Step RACH is as follows. 0 - Table 7. It allows the User Equipment (UE) to synchronize, identify itself, and request resources for uplink communication. If we assume that CRS is known to reciever in advance (e. (4) ACK + CRID (xPDCCH + xPDSCH) : Msg4 Once UE transmitted Msg3, following procedure are performed in UE and 5GNB. When I say 'communication' in this case, it means 'control command exchange' between UE and network, not the data traffic. Overall Procedure Why 2 step RACH ? Overview on Configuration RRC Parameters for (1) RR : System Information Type DLT: 147, Payload: gsm_a_ccch (GSM CCCH) GSM CCCH - System Information Type 1 L2 Pseudo Length 0101 01. 5G | ShareTechnote This site is for everything on 5G/NR Feb 24, 2024 · Dynamic Spectrum Sharing (DSS) is a feature introduced in 5G so that both LTE/4G and 5G systems can share the same spectrum. GP is not required between Uplink and Downlink, as there is less chance of collision because of the base station timing advance feature. = L2 Pseudo Length value: 21 Protocol Discriminator: Radio Resources Management messages . 5G/NR - Positioning DL Positioning Reference Signal The 5G Positioning Reference Signal (PRS) is a specialized feature introduced in 5G networks to enable advanced positioning services, offering high-accuracy location information with centimeter-level precision, a significant improvement over previous generations like 3G and 4G. However, as LTE evolves, especially as LTE tries to cover MTC or IoT related features it turned out that this max time span is not big enough to schedule all the timing related parameters (e. If the network doesn't respond before the T3410 timer expires, the UE concludes that the Attach Request has failed and TDD LTE : SR/DCI 0 Timing TDD LTE : DCI 0/PUSCH Timing TDD LTE : System Information Variation Test Loopback Mode Test/Verification : Test Methodology TFT (Traffic Flow Template) Timer (RRC) Timer (EPS Mobile Management - UE Side) Timer (EPS Mobile Management - Network Side) Timer & Constant and RRC/NAS Message Timing Advance Throughput Random Access Response (RAR): The network responds to the detected preambles, providing timing advance and resource allocation for the next step. As you see in the following figures, for Rel 8,9,10 there is no special tag for each component carrier, meaning that even in Carrier Aggregation single Timing Advanced value apply to all the component carriers. Scheduled Transmission: The device sends a message (Msg3) using the allocated resources. The figure below is an example of the resulting TDD DL-UL pattern based on these parameters. iii) Construct the resource grid from the received signal and the detected timing from step ii) NTN Requirement The technical requirements for Non-Terrestrial Networks (NTNs) are critical to ensuring their seamless integration and efficient operation alongside terrestrial communication systems. 0: Timing Advance Index: Not Present 1 . To address timing discrepancies and ensure accurate scheduling, the system incorporates a Common Timing Advance (Common TA) along with two additional timing offsets: K_offset and K_mac. (msg3) PUSCH with Temporary C-RNTI: The UE transmits a PUSCH (Physical Uplink Shared Channel) message using the temporary C-RNTI. To address this, systems need advanced techniques for reducing NTN What is it ? Why NTN ? Challenges Tech Requirements Spectrum Architecture RACH Timing Advance RRC (NR) RRC (LTE) RRC (NB IoT) Call Flow (NB IoT) 3G/UMTS Downlink Frame Timing Once you complete the cell search process described above, UE can figure out the following information about the timing. The logical channel for this message is xCCCH. TDD DL/UL Dedicated Configuration (TDD-UL-DL-ConfigDedicated) Technical Challenges Tech Viedos for 5G Test : Equipment : Concept and Idea Test : RF Connection Method Time Table (MileStones to 5G) Timing Advance Timing Units Type 0 PDCCH Common Search Space/RMSI-PDCCH-Config Type 1 PDCCH Common Search Space Waveform WhitePapers and Forums/Summits iii) UE <--NW : Random Access Response (Timing Advance, C-RNTI, UL grant for L2/L3 message) Fundamental Difference from LTE RACH As I mentioned above, the overall protocol sequence would be almost same in LTE and NR. 5G | ShareTechnote This site is for everything on 5G/NR 5G/NR - Measurement Report Measurement Report The topics I will describe in this page is higher level measurement (i. 3, 1. The variations among A1, A2, and A3 mainly address different levels of delay spread and timing advance requirements. To address this, systems need advanced techniques for reducing 3G/UMTS Downlink Frame Timing Once you complete the cell search process described above, UE can figure out the following information about the timing. This corresponds to LTE subframe duration. In UMTS case, it is true that only RRC Considerations: RACH procedures and timers need adjustments to accommodate these longer delays. We are already seeing some of the features regarded as very advanced feature in current technology (4G) but will become a kind of basic features in 5G. One of the foremost challenges is managing latency, particularly for satellites in higher orbits like Geostationary Orbit (GEO). These formats are characterized by longer sequence lengths, providing better performance in terms of timing advance measurement and detection reliability in challenging conditions: 0, 1, 2, 3: The long sequence formats are designed to support scenarios with significant delay spreads and provide reliable performance over greater distances. 100 11. It was combination of Time Domain, Frequency Domain and the modulation scheme. In many cases I had to search through many different documents just to find the meaning (full words) for those acronyms. Timing Synchronization Process: Initial Cell Search and Synchronization: The UE performs an initial cell search when it powers up or moves into a new area. i) Exact phase reference for downlink channels from CPICH (This is not the timing parameter, but this would very important factors to decode other channels including Timing/Sync related channels). E. This page will focus on user traffic flow in full details from PHY to the Highest layer. 2-1: Te Timing 2G/GSM Channel Mapping for GPRS Refer to 44. Timer (RRC) Timer (EPS Mobile Management - UE Side) Timer (EPS Mobile Management - Network Side) Timer & Constant and RRC/NAS Message Timing Advance Throughput Calculation - FDD Throughput Calculation - TDD Tracking Area Transmission Mode TTI Bundling T300 T304 T310 T3410 T3450 UCI UL Grant USIM Parameters Voice in LTE VoLTE over IMS WiFi 5G/NR - MAC CE Timing Advance The concept and functionality of NR Timing Advance is same as the LTE Timing Advance. Transparent As you see in the following figures, for Rel 8,9,10 there is no special tag for each component carrier, meaning that even in Carrier Aggregation single Timing Advanced value apply to all the component carriers. 1 Resource allocation in time domain. The major difference between LTE RACH and NR RACH would lie just before RACH Preamble gets transmitted. In cellular networks, UEs are located at varying distances from the base station, causing different signal propagation delays. ii) Exact start timing of each slots from P-SCH This timing value (let's call it as 'offset') is the crucial information to construct the accruate resource grid that is used in step iii) and onwards. But in Rel 11, the first 2 bits are allocated to indicate whether the value is for PCC or SCC. when timing advance is needed for UE positioning Two types of RACH process : Contention-based and Contention-free When a UE transmit a PRACH Preamble, it transmits with a specific pattern and this specific pattern is called a "Signature". = T3 (TBF): 37 . Test 2 : NTN with LEO This part is intended as a troubleshooting guide for all the issues you can encounter when testing LEO (Low Earth Orbit). If you just take outside looking of the device or of Basestation, you would not get any clue on what got wrong in this step. Highlevel view of the 2step RACH can be illustrated as below. In LTE (actually all other techology except NR), all the SIBs are broadcast periodically regardless of whether UE want it or not. 5G Networks Providing Access to Localized Services Smart Energy and Infrastructure Enhanced Access to and Support of Network Slices 5G Timing Resilliency System Ranging-based Service Tactile and multi-modality communication services Vehicle-Mounted Relays NTN NTN Architecture and Scenario The NTN architecture is designed to bridge the digital divide, enabling seamless connectivity across geographies where traditional ground-based networks are either impractical or economically unfeasible. Overall Sequence and Layer Configuration Downlink Channel Map Uplink Channel Map Channel Mapping Table throughout Call Processing Live Network Examples in Fullstack Overall Sequence and Layer Configuration Try to follow the sequence below This part will be described in a separate page titled Resource Allocation Type. It helps to ensure that uplink transmissions from all UE are synchronized when received by the base station. g, by specification), the reciever can use this signal to estimate [H] by comparing the received CRS and the expected CRS (the CRS specified in specification). Timing Advance Timing Units TRS (Tracking Reference Signal) Type 0 PDCCH Common Search Space/RMSI-PDCCH-Config Type 1 PDCCH Common Search Space Type 2 PDCCH Common Search Space Type 3 PDCCH Common Search Space Two Step RACH (2 step RACH) UAC (Unified Access Control) UCI (Uplink Control Information) UDM UE Assistance Information UE Capability UE ID After the connection is established, gNB would re adjust timing advance periodically to maintain the connection by sending Timing Advance MAC CE. : P0: Not Present . 4G/LTE - Timers T3410, T3450 T3410 and T3450 are the timer involved in Initial Attach procedure. = Skip Indicator: No indication of selected PLMN (0) Message Type: System The eNB sends a Random Access Response (RAR), including timing advance information, uplink grant, and a temporary C-RNTI for the UE. This timing advance ensures that signals from the UE arrive at the base station synchronized with the base station's receive window, taking into account the round-trip delay. 060 - 1. both gNB Rx to Tx switch and UE Tx to Rx switch are adjusted in UL advance only. g. CHO addresses this problem by shifting the execution timing from the network to the UE. Network (eNodeB in this case) keep measuring the time difference between PUSCH/PUCCH/SRS reception and the subframe time and can send a 'Timing Advance' command to UE to change the PUSCH/PUCCH transmission to make it better aligned with the subframe timing at 6G 6G Timeline Currently (as of Jan, 2025) there is not specific time line defined by 3GPP yet, but at least we start seeing some meaningful proposals from various sources. e, RRC layer measurement), but this higher layer measurement is based on very complicated lower layer process. : TBF Starting Time: Present . ta-Report-r17 : enable/disable UE specific TA report, t318-r17 : Radio Link Failure (RLF) related timer UE Timers and Constants: Various timers and constants that control UE behavior. See full list on sharetechnote. e, configuration for a specific UE, not common TDD LTE : SR/DCI 0 Timing TDD LTE : DCI 0/PUSCH Timing TDD LTE : System Information Variation Test Loopback Mode Test/Verification : Test Methodology TFT (Traffic Flow Template) Timer (RRC) Timer (EPS Mobile Management - UE Side) Timer (EPS Mobile Management - Network Side) Timer & Constant and RRC/NAS Message Timing Advance Throughput Dec 17, 2021 · It would shorten the signaling time greatly and I can even shorten the required timing for PUSCH transmission since PUSCH can be transmitted at the first step (Step 1) of the process. < Normal Burst > This burst format is used by all other channels (except FCCH, SCH, RACH and AGCH). The network prepares the handover in advance and provides the target information and the execution condition. Timing Advance Timing Units TRS (Tracking Reference Signal) Type 0 PDCCH Common Search Space/RMSI-PDCCH-Config Type 1 PDCCH Common Search Space Type 2 PDCCH Common Search Space Type 3 PDCCH Common Search Space Two Step RACH (2 step RACH) UAC (Unified Access Control) UCI (Uplink Control Information) UDM UE Assistance Information UE Capability UE ID 3G/UMTS-TDSCDMATiming Advance The FACCH channel uses this burst during handover operation (when the timing advance of new cell is not yet known). 211 - Figure 4. [Sharetechnote] does it mean that UE should start transmitting PUCCH at (the start symbol time of PUCCH - switching time) as well ? [Sakshama] yes true. Simply put, Timing Advance is a special command (notification) from eNB to UE that enable UE to adjust its uplink transmission as shown 3G/UMTS-TDSCDMATiming Advance 4G/LTE - LTE Advanced PUCCH When you are thinking of LTE Advanced, the first feature you would think would be `Carrier Aggregation`. = T1' (TBF): 19 . Then the question is 'can the reciever decode User data (d) only with knowledge of [H] ?'. Jun 30, 2025 · What is Timing Advance? Timing Advance is a mechanism to compensate for propagation delays in uplink transmissions. In each LTE cell, total 64 preamble signatures are available and UE select randomly one of these Considerations: RACH procedures and timers need adjustments to accommodate these longer delays. qvvo lvmvk hckt oxpf fixic uvlgl bqta bgboh hssp fwqw xgqnk hlooa drib vhyym ladf