Contents
What is LoRa code rate?
The coding rate refers to the proportion of transmitted bits that actually carry information. Coding rate can be 6/8, 4/8, etc… So if CR is 4/8 we are transmitting twice as many bits as the ones containing information.
How long is a LoRa chirp?
The bandwidth is the most important parameter of the LoRa modulation. A LoRa symbol is composed of 2SF chirps, which cover the entire frequency band.
Is there a chip rate for 95?
The second-generation mobile telephony version of CDMA is based on the IS-95 standard and uses a 1.2288 MHz chip rate DSSS QPSK signal in a 1.25 MHz wide channel.
What is a chirp in LoRa?
Chirp stands for ‘Compressed High Intensity Radar Pulse’. It is a signal which frequency either increase or decrease with time. It is very common is sonar and radar. It is also used in spread spectrum.
What is chip error rate?
The Bit Error Rate is a system level performance indicator as against the Chip Error Rate, which is more directly a circuit performance indicator as it measures the SNR (Signal to Noise Ratio) at the ADC. Thus, the simulation results at the system level indicate an almost equal performance for all three architectures.
What is the chip rate of W CDMA?
Explanation: W-CDMA uses a chip rate of 3.84 Mcps. Chip rate is the product of symbol rate and spreading factor. If the symbol rate is 960 Kbps and spreading factor is 4 for W-CDMA, then the chip rate is 3.84 Mcps.
What are chips in digital communication?
In digital communications, a chip is a pulse of a direct-sequence spread spectrum (DSSS) code, such as a pseudo-random noise (PN) code sequence used in direct-sequence code division multiple access (CDMA) channel access techniques.
What is a chipping rate?
In direct sequence spread spectrum technologies such as DSSS and CDMA, it is the number of bits per second (chips per second) used in the spreading signal. Chip rate is measured in “megachips per second” (Mcps), which is millions of chips per second.
What’s the difference between a Lora and a chirp?
LoRa is a chirp-based spread-spectrum modulation. A symbol is a chirp. To generate symbols/chirps, the modem modulates the phase of an oscillator. The number of times per second that the modem adjusts the phase is called the chip rate and defines the modulation bandwidth.
What is the spreading factor and bandwidth in Lora?
As discussed before, LoRa is a chirp spread spectrum modulation. The transmitted data, which is a symbol, will be represented by a chirp signal with a frequency range from to , which is shown in Figure 1. In LoRa modulation, we can configure the symbol by changing the Spreading Factor and Bandwidth parameters.
Which is the coding rate for LoRa modulation?
In the implementation of the LoRa modulation, every 4 bits of data will be encoded as 5, 6, 7, or 8 total bits as a form of forward error correction, and these are selected by setting the coding rate CR = 1, 2, 3, 4. So the actual rate of user data bits must be reduced by the factor: B R u s e r = B R 4 4 + C R.
What is the range of the Lora signal?
LoRa Signal Spectrogram through SDR reading (source: DecodingLora) As discussed before, LoRa is a chirp spread spectrum modulation. The transmitted data, which is a symbol, will be represented by a chirp signal with a frequency range from to , which is shown in Figure 1.