Board-dat/NGS/NGS1131-DAT/NGS1131-DAT.md
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# NGS1131 DAT
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- [[A7670-DAT]]
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+
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- https://www.electrodragon.com/product/a7670-lte-cat-1-gsm-mini-module/?attribute_pa_simcom=a7670c
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![](15-36-16-05-01-2023.png)
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+## ref
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+
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+- [[M2M-dat]] - [[SIMCOM-dat]]
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Chip-cn-dat/SIMCOM-dat/A7670-DAT/A7670-DAT.md
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* Default baudrate is 115200
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+
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## Hardware Design
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### Power Supply
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当电源能够提供 1A 的持续电流时，外部供电电容总容值，建议不小于 200uF；若不能提供 1A 的持续电流，则建议外部电容总容值不小于 600uF，以保证任何时候 VBAT 上电压跌落不超过 300mV。
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+## A7670
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+
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+| module suffix | FDD | TDD |
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+| ------------- | ---------------------------- | ------------------- |
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+| C | B1/B3/B5/B8 | B34/B38/B39/B40/B41 |
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+| E | B1/B3/B5/B7/B8/B20 | B34/B38/B39/B40/B41 |
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+| SA | B1/B2/B3/B4/B5/B7/B8/B28/B66 | B34/B38/B39/B40/B41 |
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+
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+
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## ref
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* demo video to boot and use with USB here https://w.electrodragon.com/w/Demo_Video
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+
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+- [[NGS1131-dat]]
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+
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- [[SIMCOM-dat]]
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- [[SIMCOM]] - [[A7670]]
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Tech-dat/Network-dat/M2M-dat/2024-07-03-18-08-51.png
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Binary files /dev/null and b/Tech-dat/Network-dat/M2M-dat/2024-07-03-18-08-51.png differ
Tech-dat/Network-dat/M2M-dat/M2M-dat.md
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LTE FDD B1/B3/B5/B7/B8/B20/B28
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LTE TDD B34/B38/B39/B40/B41
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+
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+- Frequency-division duplexing (FDD);
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+- time-division duplexing (TDD)
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+
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+
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CAT-M
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CAT-NB
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| Positioning | Cell ID | OTDOA, E-CID |
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+
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+## CAT-M
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+
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+CAT-M (also known as LTE-M or LTE Cat-M1) can operate in both Frequency Division Duplex (FDD) and Time Division Duplex (TDD) modes. The choice between FDD and TDD for CAT-M depends on the specific network deployment and regional spectrum regulations.
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+
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+### Overview
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+Frequency Division Duplex (FDD): Uses separate frequencies for uplink and downlink. It allows for simultaneous transmission and reception.
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+Time Division Duplex (TDD): Uses the same frequency for both uplink and downlink but alternates in time. Transmission and reception occur at different times on the same frequency.
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+
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+### CAT-M Characteristics
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+Compatibility: CAT-M is designed to be compatible with existing LTE infrastructure, so it can utilize FDD, which is more commonly used in LTE networks.
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+
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+Flexibility: CAT-M also supports TDD for regions or deployments where TDD is preferred or necessary due to spectrum availability or regulatory reasons.
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+
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+### Practical Use
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+FDD: Predominantly used in regions where FDD LTE networks are prevalent. Common in many parts of the world due to existing LTE deployments.
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+TDD: Used in regions or specific cases where TDD LTE networks are implemented, offering flexibility in spectrum usage and often used in China and some other areas.
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+If you're deploying or using CAT-M technology, check with the specific network provider or region's spectrum regulations to understand which mode is supported.
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+## FDD vs TDD
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+
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+- https://en.wikipedia.org/wiki/LTE_frequency_bands
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+- TDD mainly located at 34 ~ 54
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+
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+## Support
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+
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+- check supported countries by here: https://en.wikipedia.org/wiki/List_of_LTE_networks
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+- check by sepcific country: https://www.frequencycheck.com/countries
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+- interactive map: https://worldpopulationreview.com/country-rankings/lte-bands-by-country
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+![](2024-07-03-18-08-51.png)
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## Functions
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LBS = Base station location, AT+CLBS