In this video, discover how 5G's Flexible Numerology revolutionizes wireless communication, enabling faster speeds and more efficient connections. Unlike LTE, which uses a fixed 15kHz subcarrier spacing, 5G offers variable subcarrier spacing from 15kHz to 240kHz, adapting to different environments and use cases. Learn why flexible numerology is critical for:
* Lower latency: Smaller slot durations allow faster data transmission.
* Better coverage: Tailored subcarrier spacing for both outdoor macrocells and indoor deployments.
* High-speed connections: Higher subcarrier spacing improves performance in millimeter-wave bands.
* Adaptation to different environments: From urban centres to rural areas, 5G adjusts to various cell sizes and frequency bands.
* Enhanced network efficiency: Flexible numerology optimizes data flow, ensuring smoother connectivity even in high-demand areas.
You’ll also learn:
* Key differences between LTE and NR frame structures
* Why different subcarrier spacing is necessary for 5G networks
* The significance of Delay Spread and Coherence Time in 5G
* How flexible numerology enhances data transmission for faster, more reliable connections
* Real-world applications, from macrocells using 15kHz subcarrier spacing to millimeter-wave bands with 120kHz spacing
We’ll explain essential concepts like delay spread and coherence time, and how they influence symbol duration, making 5G adaptable to large cell sizes and fast-moving users. With flexible numerology, 5G becomes more efficient, versatile, and capable of meeting the needs of the future.
Watch to see how this critical feature powers the next generation of wireless networks!
Subscribe to "Learn And Grow Community"
YouTube : https://www.youtube.com/@LearnAndGrowCommunity
LinkedIn Group : https://linkedin.com/company/LearnAndGrowCommunity
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#5g #5gnetworks #FlexibleNumerology #wirelesstechnology #techexplained #5GInnovation #FutureofConnectivity #5gspeed #SubcarrierSpacing #5gnetwork #5grevolution #5gnr #5gnsa #5gsa #5gservices #3gpp #numerology #subcarrierspacing #SCS #5gbandwidth #5gdeployment #5gconnectivity #5gran #5gcore #5gvs4g #4gvs5g
* Lower latency: Smaller slot durations allow faster data transmission.
* Better coverage: Tailored subcarrier spacing for both outdoor macrocells and indoor deployments.
* High-speed connections: Higher subcarrier spacing improves performance in millimeter-wave bands.
* Adaptation to different environments: From urban centres to rural areas, 5G adjusts to various cell sizes and frequency bands.
* Enhanced network efficiency: Flexible numerology optimizes data flow, ensuring smoother connectivity even in high-demand areas.
You’ll also learn:
* Key differences between LTE and NR frame structures
* Why different subcarrier spacing is necessary for 5G networks
* The significance of Delay Spread and Coherence Time in 5G
* How flexible numerology enhances data transmission for faster, more reliable connections
* Real-world applications, from macrocells using 15kHz subcarrier spacing to millimeter-wave bands with 120kHz spacing
We’ll explain essential concepts like delay spread and coherence time, and how they influence symbol duration, making 5G adaptable to large cell sizes and fast-moving users. With flexible numerology, 5G becomes more efficient, versatile, and capable of meeting the needs of the future.
Watch to see how this critical feature powers the next generation of wireless networks!
Subscribe to "Learn And Grow Community"
YouTube : https://www.youtube.com/@LearnAndGrowCommunity
LinkedIn Group : https://linkedin.com/company/LearnAndGrowCommunity
Follow #LearnAndGrowCommunity
#5g #5gnetworks #FlexibleNumerology #wirelesstechnology #techexplained #5GInnovation #FutureofConnectivity #5gspeed #SubcarrierSpacing #5gnetwork #5grevolution #5gnr #5gnsa #5gsa #5gservices #3gpp #numerology #subcarrierspacing #SCS #5gbandwidth #5gdeployment #5gconnectivity #5gran #5gcore #5gvs4g #4gvs5g
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LearningTranscript
00:00Hi, in the last session, we talked about 12 connectivity and we seen that how it can improve
00:06the user throughput and how it can improve the user experience for better throughput
00:11to fast load balancing and improved mobility robustness.
00:15Now in this session, we will explore the concept of flexible numerology in 5G, we will understand
00:22that why it is important and we will see that how it works within the network.
00:27Let's begin by looking at the LTE frame structure and then we will compare it with the 5G NR
00:33frame structure to understand the differences and improvements.
00:37Similar to LTE, the NR frame in 5G is also 10ms long.
00:43So this frame length is common for both the technologies.
00:46Today, LTE supports carrier bandwidth of up to 20MHz and it uses a fixed OFDM numerology
00:55with consistent parameters across the network.
00:58LTE employs a 15kHz spacing between OFDM subcarriers and this is standard across the whole LTE network.
01:06LTE frames are divided into two slots.
01:09Each slot has 0.5ms and each slot contains 6 or 7 OFDM symbols.
01:16So in LTE, the symbol duration is approximately 66us which is same across all LTE deployments.
01:24Now when designing a new era interface like 5G, it's important to carefully select an
01:30appropriate symbol duration to optimize the performance.
01:33But before that, let's understand two important concepts that affect symbol duration.
01:39These concepts are delay spread and coherence time.
01:43Both of them are important concepts in wireless communications.
01:47Delay spread refers to the time difference between when the first and last significant
01:52signal reflection arrives at the receiver due to multipath propagation.
01:57So if you send an impulse in the ear, then there is a concept called multipath effect.
02:03So when this impulse is transmitted, it takes various parts and reflections to reach at the
02:09receiver.
02:10And because they are reflecting from different surfaces and follow different paths, this one
02:15signal impulse reaches at the receiver in multiple pulses.
02:19And because of different paths, they arrive at the receiver with slightly different times.
02:25This variation in the arrival times is named as delay spread which is a key factor in wireless
02:31communication.
02:32Larger cells usually experience higher delay spread.
02:36So a delay spread is the gap of duration between the first receiving impulse and last receiving
02:41pulse.
02:42Now let's discuss coherence time.
02:45So coherence time refers to the time period during which the characteristics of a communication
02:50channel remains relatively constant.
02:53It is the duration over which the channel response is stable.
02:57Means it does not change significantly.
03:00Higher frequency bands and faster moving user equipments or UEs typically result in shorter
03:06coherence time due to rapid change in the channel conditions.
03:10Now the concept is to ensure the reliable communication, the symbol duration should be
03:15shorter than the coherence time and significantly longer than the delay spread.
03:20And from the 5G spectrum, we've seen that 5G supports multiple frequency bands, including
03:26multimeter bands.
03:28Now 5G is expected to support a wide range of frequency bands and various cell sizes and
03:35fast moving user equipment.
03:37Now because of this diversity, a single symbol duration is insufficient to meet all these
03:42needs of different scenarios.
03:44So we are needing additional flexibility to select the symbol duration.
03:48And to address this, 5G NR introduces flexible numerology.
03:53Now that allows various symbol durations to match the different use cases and network
03:58conditions.
04:00Like LTE, 5G NR also have a 10 millisecond frame structure.
04:04But now it has added more flexibility in the subcarrier spacing.
04:08Means unlike LTE, 5G NR supports a range of subcarrier spacing.
04:14That is from 15 kHz to 240 kHz.
04:17So that provides more adaptability for the different scenarios.
04:22Although this picture here only shows up to 120 kHz.
04:26But please remember that NR can support up to 240 kHz subcarrier spacing for even more
04:32flexibility.
04:33Each NR subframe is still limited to 14 OFDM symbols.
04:37Just like we have LTE.
04:39But 5G can adjust the subcarrier spacing.
04:43So the number of symbols per frame is fixed at 14.
04:46But the duration of each slot decreases as the subcarrier spacing increases.
04:51So it allows faster data transmission.
04:54And hence, larger subcarrier spacing helps in reducing latency as well.
04:59Because it allows data to be transmitted in a shorter slot duration.
05:04Which is crucial for time sensitive applications.
05:07This kind of flexibility brings a better configuration for different types of deployments.
05:12According to their most suitable properties.
05:15For example, outdoor microcells operating on the lower frequency bands like 700 MHz can
05:22use 15 kHz subcarrier spacing.
05:24Which is better suited for the environments with high multipath interference.
05:29Mid-sized indoor deployments can use 30 kHz or 60 kHz subcarrier spacing.
05:35Due to their smaller cell size and the need of efficient spectrum uses.
05:40Although mmWave deployments which offer extremely high bandwidths.
05:45They require careful selection of subcarrier spacing.
05:49So if you use smaller subcarrier spacing in these high frequency bands.
05:53Then the FFT computation or Fast Fourier Transform computations can be more complex
05:58and challenging.
06:00In addition, they also have smaller cell sizes.
06:03So a higher subcarrier spacing suits them better.
06:07Okay, so that's it for today.
06:08I believe now you have some basic understanding on 5G NR, flexible numerology and how to use
06:14it in network for better performance and for better user experience.
06:18This was also one of the major updates in 5G NR network.
06:22Compared to the legacy 4G ALT network.
06:25In the next session, we will be talking about mini slots, preemptive scheduling and self-contained
06:31slots in 5G.
06:32So stay tuned for the updates.
06:34If you did not subscribe till now, then please do subscribe to learn and grow community for
06:38regular updates.
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