Contents
Which modulation technique is used by LoRa?
spread spectrum modulation
LoRa RF physical layer uses a form of spread spectrum modulation. The LoRa modulation scheme uses wide-band linear frequency modulated pulses. The level of frequency increase or decrease over time is used to encode the data to be transmitted, i.e. a form of chirp modulation.
How does LoRa transmit data?
A LoRaWAN gateway receives LoRa modulated RF messages from any end device in hearing distance and forwards these data messages to the LoRaWAN network server (LNS), which is connected through an IP backbone. There is no fixed association between an end device and a specific gateway.
What is bandwidth in LoRa?
In most cases LoRaWAN uses LoRa modulation. LoRaWAN can use channels with a bandwidth of either 125 kHz, 250 kHz or 500 kHz, depending on the region or the frequency plan. The spreading factor is chosen by the end-device and influences the time it takes to transmit a frame.
How does LoRa communication work?
LoRa works by moving an RF tone around over time in a very linear way. This graph shows the chirps in a reverse waterfall—the newest data is at the top, which is called an “up chirp.” You can see how this frequency of the tone is increasing over time.
What is LoRa good for?
While 5G may be optimal for video calls or ultra-low latency applications, networks based on LoRa are ideal for water and gas metering, asset tracking, homes and buildings, and many more applications where low power consumption, long range and the ability to penetrate physical structures are required.
How is the spreading of the spectrum achieved in Lora?
In LoRa modulation, the spreading of the signal’s spectrum is achieved by generating a chirp signal that continuously varies in frequency, as is depicted in Figure 5. An advantage of this method is that the timing and frequency offsets between transmitter and receiver are equivalent, greatly reducing the complexity of the receiver design.
How many spreading factors are used in LoRa modulation?
In LoRa terms, the amount of spreading code applied to the original data signal is called the spreading factor(SF). LoRa modulation has a total of six spreading factors (SF7 to SF12). The larger the spreading factor used, the farther the signal will be able to travel and still be received without errors by the RF receiver.
What are the features of a Lora gateway?
A LoRa Gateway has the ability to simultaneously receive and broadcast messages with different SF (spreading factors). The LoRa specific architecture is composed of end nodes and Gateway modules that retransmit messages from the terminal nodes to the Network Server.
What’s the data transfer rate of a Lora gateway?
The data transfer rate varies from 300 bps to 37.5 kbps, depending on the spreading factor and the bandwidth of the communication channel. A LoRa Gateway has the ability to simultaneously receive and broadcast messages with different SF (spreading factors).