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Wireless Temperature and Humidity Presentation Slides Wireless Monitoring for GxP & Controlled Environments Learn about Modern RF Communication using VaiNet as an example Paul Daniel Sr. GxP Regulatory Expert [email protected] © Vaisala Vaisala in Brief . We serve customers in weather and controlled environment markets . 80 years of experience in providing a comprehensive range of innovative observation and measurement products and services © Vaisala 2 Vaisala in Brief . We serve customers in weather and controlled environment markets . 80 years of experience in providing a comprehensive range of innovative observation and measurement products and services © Vaisala 3 Vaisala in Brief . We serve customers in weather and controlled environment markets . 80 years of experience in providing a comprehensive range of innovative observation and measurement products and services © Vaisala 4 Wireless Monitoring for GxP & Controlled Environments Learn about Modern RF Communication using VaiNet as an example Paul Daniel Sr. GxP Regulatory Expert [email protected] © Vaisala © Vaisala 6 Goals . Learn: Communication Technology Basics . Radio waves, Modulation, and Link Budgets . Explore: Internet of Things . LoRa® Technology . VaiNet Architecture . Connectivity for Monitoring . Ethernet, VaiNet, Wi-Fi, Bluetooth, ZigBee © Vaisala 7 Internet Evolution: Servers and Clients © Vaisala 8 Wired: Ethernet . Range: . Less than 100m . Power: . Available as PoE (Power over Ethernet) . Security: . Physical network access required . Reliability: . Wired full duplex connections are reliable . Flexibility: . Hard to move network drops . Investment: . One drop per sensor © Vaisala 9 Internet Evolution: Wireless © Vaisala 10 Wireless: Wi-Fi . Range: . Maximum 20m . Power: . High power required . Security: . Difficult to secure . Reliability: . Signal strength can change . Flexibility: . High flexibility . Investment: . Wi-Fi Access Points only © Vaisala 11 Internet Evolution: Things © Vaisala 12 Wireless: VaiNet . Range: . LoRa Modulation on 868 or 915 MHz achieves 100+ meters . Power: . Low energy LoRa® signal means sensor needs only 2 AA batteries . Security: . Low bitrate “invisible” encrypted signal on segregated network. Reliability: . Resilient topology and LoRa modulation maintains connectivity. Flexibility: . VaiNet Access point is only fixed asset. Investment: . One VaiNet Access Point for 32 sensors © Vaisala 13 © Vaisala 14 © Vaisala 15 © Vaisala 16 Radio Waves © Vaisala 17 Frequency . Hertz = Hz . 1 Hz = 1 cycle/second . Wireless Communication Frequencies . 2.4 GHz . 900 MHz © Vaisala 18 Frequency . Hertz = Hz . 1 Hz = 1 cycle/second . Wireless Communication Frequencies . 2.4 GHz . 900 MHz © Vaisala 19 Wavelength . As frequency gets higher… . Wavelength gets shorter… – Signal must oscillate more times in the same distance – Energy is lost with each oscillation! . Longer wavelength can curve around obstacles. © Vaisala 20 Wavelength . As frequency gets higher… . Wavelength gets shorter… – Signal must oscillate more times in the same distance – Energy is lost with each oscillation! . Longer wavelength can curve around obstacles. © Vaisala 21 Wavelength . As frequency gets higher… . Wavelength gets shorter… – Signal must oscillate more times in the same distance – Energy is lost with each oscillation! . Longer wavelength can curve around obstacles. © Vaisala 22 ISM Bands (Industrial, Scientific, Medical) . 2.4 GHz . ISM Worldwide – Microwave Ovens – Wi-Fi – Bluetooth . “900 MHz” . 915 MHz – Americas Only . 868 MHz – Europe Only © Vaisala 23 Basic Modulation . Modulation . Slight changes to the signal to encode information. Old school modulation: • AM = Amplitude Modulation • FM = Frequency Modulation . Modulation makes it easier to find the signal in the noise! © Vaisala 24 Basic Modulation . Modulation . Slight changes to the signal to encode information. Old school modulation: • AM = Amplitude Modulation • FM = Frequency Modulation . Modulation makes it easier to find the signal in the noise! © Vaisala 25 Spread Spectrum Modulation . Signal is spread over multiple neighboring frequencies. Each part of the message is on a slightly different frequency. Message is more robust and resists interference. ABCDE ABCDE A D B C E © Vaisala 26 Spread Spectrum Modulation . Signal is spread over multiple neighboring frequencies. Each part of the message is on a slightly different frequency. Message is more robust and resists interference. ABCDE ABCDE A D B C E © Vaisala 27 Common Spread Spectrum Types . Frequency Hopping (FHSS) . Hopping Sequence known to devices – Common use: Bluetooth . Direct Sequence (DSSS) . Message is spread mathematically with coding sequence in message. – Common use: Wi-Fi ABCDE ABCDE A D B C E © Vaisala 28 Common Spread Spectrum Types . Frequency Hopping (FHSS) . Hopping Sequence known to devices – Common use: Bluetooth . Direct Sequence (DSSS) . Message is spread mathematically with coding sequence in message. – Common use: Wi-Fi ABCDE ABCDE A D B C E © Vaisala 29 Link Budget = Tx –Rx . Transmission Power (Tx) = +15 dBm . Receiver Sensitivity (Rx) = -80 dBm . Link Budget = 95 dBm 15 0 -75 -80 Rx Sensitivity © Vaisala 30 Link Budget = Tx –Rx . Transmission Power (Tx) = +15 dBm . Receiver Sensitivity (Rx) = -80 dBm . Link Budget = 95 dBm Obstacle -20 dBm 15 0 Distance -10 dBm -75 -80 Rx Sensitivity © Vaisala 31 Link Budget = Tx –Rx . Transmission Power (Tx) = +15 dBm . Receiver Sensitivity (Rx) = -80 dBm . Link Budget = 95 dBm Obstacle -20 dBm 15 Obstacle 0 Distance -20 dBm -10 dBm Distance -10 dBm -75 -80 Rx Sensitivity © Vaisala 32 Link Budget = Tx –Rx . Transmission Power (Tx) = +15 dBm . Receiver Sensitivity (Rx) = -80 dBm . Link Budget = 95 dBm Obstacle -20 dBm 15 Obstacle 0 Distance -20 dBm -10 dBm Obstacle Distance -20 dBm -10 dBm Distance -10 dBm -75 -80 Rx Sensitivity © Vaisala 33 Link Budget = Tx –Rx . Transmission Power (Tx) = +15 dBm . Receiver Sensitivity (Rx) = -80 dBm . Link Budget = 95 dBm Obstacle -20 dBm 15 Obstacle 0 Distance -20 dBm -10 dBm Obstacle Link Losses Distance -20 dBm 90 dBm -10 dBm Distance -10 dBm -75 -80 Rx Sensitivity © Vaisala 34 Link Budget = Tx –Rx . Transmission Power (Tx) = +15 dBm . Receiver Sensitivity (Rx) = -80 dBm . Link Budget = 95 dBm Obstacle -20 dBm 15 Obstacle 0 Distance -20 dBm -10 dBm Obstacle Link Losses Distance -20 dBm 90 dBm -10 dBm Distance -10 dBm -75 Link Margin 5 dBm -80 Rx Sensitivity © Vaisala 35 Link Budget = Tx –Rx . Transmission Power (Tx) = +15 dBm . Receiver Sensitivity (Rx) = -80 dBm . Link Budget = 95 dBm Obstacle -20 dBm 15 Obstacle 0 Distance -20 dBm -10 dBm Obstacle Link Losses Distance -20 dBm 90 dBm -10 dBm Distance -10 dBm -75 Link Margin 5 dBm -80 Rx Sensitivity © Vaisala 36 Radio Waves Summary . Frequency and Wavelength . High frequency = More data . Low frequency = Longer range . Basic Modulation . Encodes information in signal . Spread Spectrum Modulation . Makes signal visible in the noise . Link Budget . Defines how far a signal can potentially travel – Additional modulation can increase the Link Budget © Vaisala 37 © Vaisala 38 VaiNet: An introduction in two Parts . LoRa™ Frequency Modulation . Vaisala Network Architecture © Vaisala 39 LoRa Part 1: 868/915 MHz . 868 MHz (Europe) / 915 MHz (Americas) . Lower frequency with longer wavelength . Relatively empty frequency: – 2.4 GHz has higher data rate – 2.4 GHz is ISM worldwide . Advantage . Disadvantage . Great range . Low bitrate . Uncrowded . Must make frequency two devices: has less – 868 MHz (Europe) interference – 915 MHz (Americas) © Vaisala 40 LoRa Part 1: 868/915 MHz . 868 MHz (Europe) / 915 MHz (Americas) . Lower frequency with longer wavelength . Relatively empty frequency: – 2.4 GHz has higher data rate – 2.4 GHz is ISM worldwide . Advantage . Disadvantage . Great range . Low bitrate . Uncrowded . Must make frequency two devices: has less – 868 MHz (Europe) interference – 915 MHz (Americas) © Vaisala 41 LoRa Part 1: 868/915 MHz . 868 MHz (Europe) / 915 MHz (Americas) . Lower frequency with longer wavelength . Relatively empty frequency: – 2.4 GHz has higher data rate – 2.4 GHz is ISM worldwide . Advantage . Disadvantage . Great range . Low bitrate . Uncrowded . Must make frequency two devices: has less – 868 MHz (Europe) interference – 915 MHz (Americas) © Vaisala 42 © Vaisala 43 VaiNet adds Modulation . Chirp Spread Spectrum Up-Chirp . Spread Pattern not required – Resists Multi-Path Fading Down-Chirp – Highly Secure with added AEP No Chirp . LoRa Modulation . Continuous Chirps – Chirps not Discrete . Orthogonal Spreading – Overlay Multiple Transmissions © Vaisala 44 VaiNet adds Modulation . Chirp Spread Spectrum Up-Chirp . Spread Pattern not required – Resists Multi-Path Fading Down-Chirp – Highly Secure with added AEP No Chirp . LoRa Modulation . Continuous Chirps – Chirps not Discrete . Orthogonal Spreading – Overlay Multiple Transmissions © Vaisala 45 VaiNet adds Modulation . Chirp Spread Spectrum Up-Chirp . Spread Pattern not required – Resists Multi-Path Fading Down-Chirp – Highly Secure with added AEP No Chirp . LoRa Modulation . Continuous Chirps – Chirps not Discrete . Orthogonal Spreading – Overlay Multiple Transmissions © Vaisala 46 VaiNet adds Modulation . Chirp Spread Spectrum Up-Chirp . Spread Pattern not required – Resists Multi-Path Fading Down-Chirp – Highly Secure with added AEP No Chirp . LoRa Modulation . Continuous Chirps – Chirps not Discrete . Orthogonal Spreading – Overlay Multiple Transmissions © Vaisala 47 © Vaisala 48 © Vaisala 49 © Vaisala 50 © Vaisala 51 © Vaisala 52 VaiNet Architecture © Vaisala
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