Simply put, Bluetooth is a short-range broadband radio technology that is a global open standard for wireless transmission of voice and data. It uses advanced techniques such as frequency hopping spread spectrum (FHSS), time division multiple access (TDMA), and code division multiple access (CDMA) to establish information transmission between multiple communication and information systems in a small area. The main technical features of Bluetooth: (1) Working frequency band: 2.4GHz industrial technology (ISM) frequency band, no need to apply for a permit. Most countries use 79 frequency points, the carrier frequency is (2402+k) MHz (k=0, 1, 2...78), and the carrier frequency is 1MHz. Adopt TDD time division duplex mode. (2), transmission rate: 1Mb / s (V2.0 or higher version) (3) Debugging mode: GFSK modulation with BT=0.5, modulation index is 0.28-0.35. (4) Adopting frequency hopping technology: the frequency hopping rate is 1600 hops/second, which is increased to 3200 hops/second when building the chain (including paging and query). Bluetooth reduces co-channel interference through fast frequency hopping and short packet technology to ensure transmission reliability. (5), voice modulation mode: continuous variable slope incremental modulation (CVSD, ConTInuousVariableSlope Delta ModulaTIon), strong anti-fading, even if the bit error rate reaches 4%, the voice quality is acceptable. (6) Support circuit switching and packet switching services: Bluetooth supports real-time synchronous directional connection (SCO link) and non-real-time asynchronous non-directional connection (ACL link). The former mainly transmits real-time information such as voice, and then The data is mainly based on data packets. Voice and data can be transmitted separately or simultaneously. Bluetooth supports an asynchronous data channel, or three concurrent synchronous voice channels, or a channel that simultaneously transmits asynchronous data and synchronized voice. Each voice channel supports 64 kbps of synchronous voice; the asynchronous channel supports 723.2/57.6 kbps asymmetric duplex communication or 433.9 kbps symmetric full duplex communication. (7) Supporting point-to-point and point-to-multipoint communication: Bluetooth devices can form two networks in a specific way: piconet and distributed network (Scatternet), where the establishment of the piconet begins with the connection of two devices. It can consist of up to eight devices. In a piconet, only one master device (Master) and the other slave devices (Slave), different master and slave device pairs can adopt different link modes, and the link mode can be arbitrarily changed in one communication. Several independent piconets are linked together in a specific way to form a distributed network. All Bluetooth devices are peer-to-peer, so there is no concept of a base station in Bluetooth. (8) Working distance: The Bluetooth device is divided into three power levels: 100mW (20dBm), 2.5mW (4dBm) and 1mW (0dBm). The corresponding effective working range is: 100m, 10m and 1m. . Outdoor Solar String Light,Durable Light Stringer,Rechargeable String Light,Led String Outdoor DONGGUAN JIANXING LIGHTING ELECTRIC APPLIANCES CO., LTD , https://www.rslightstring.com
Solar Outdoor String Light set is waterproof and durable.
Can be used in any season and many applications such as wedding, party,
garden etc. We have different wire model and Replacement Bulb type to
choose.
Decorative string
lights are not just for holidays anymore . Instantly transform indoor
and outdoor spaces with a wide selection of covers and finishes that match current trends and personal tastes and expressions.
Celebrate any season ,event or inspired whim with a charming new set of outdoor string lights!