Adaptive frequency-hopping spread spectrum (AFH) AFH is used in Bluetooth wireless technology to improve resistance toradio frequencyinterference by circumventing high-traffic frequencies in the hopping sequence. This type of adaptive transmission is simpler to implement with FHSS than with DSSS. Chirp modulation Chirpmod...
Frequency hopping spread spectrum is defined in the 2.4 GHz band and operates in around 79 frequencies ranging from 2.402 GHz to 2.480 GHz. Every frequency is GFSK modulated with channel width of 1MHz and rates defined as 1 Mbps and 2 Mbps respectively. Techopedia Explains Frequency Hopping Spr...
One way in which spread spectrum is implemented is through frequency hopping, a technique in which a signal is transmitted in short bursts, “hopping” between frequencies in a pseudo-random sequence. Both the transmitting device and the receiving device must be aware of the frequency sequence. ...
The direct sequence spread spectrum (DSSS) technology has advantages in high-reliability applications, whereas the frequency hopping spread spectrum (FHSS) technology has advantages in low-cost applications. Generally, DSSS fast transmits data in full-band mode, and allows for a h...
Multi-path is commonly considered to be a mobile wireless communications problem, but even in the absence of motion, the changing wavelengths inherent in frequency-hopping systems create the environment for stationary installations to experience multi-path fading. Some channels in the license-free ...
The idea of spread spectrum communications originated in1900whenNikola Teslaproposed a similar technique called frequency hopping. Commercial use of spread spectrum began in the 1980s, and theFCC(Federal Communications Commission) allowed for unlicensed use of spread spectrum communications starting in1985...
Bluetooth devices use the frequency hopping spread spectrum (FHSS) technology and 1 MHz channel bandwidth. If a bluetooth device is sending data at the frequency band overlapping with a WLAN channel that is being monitored by a WLAN device, the WLAN device selects a rando...
The constant frequency switching that Bluetooth uses is known asfrequency-hopping spread spectrum.This technology makes Bluetooth highly secure because the signals are resistant to interference, hard to intercept by third parties, and difficult to jam. Plus, they can co-exist with conventional signals...
• It is a low power system that uses 2.4 GHz ISM band in a range of 10 meters. • This band is divided into 79 channels of 1MHz each. Bluetooth uses the Frequency Hopping Spread Spectrum (FHSS) method in the physical layer to avoid interference from other devices or networks. •...
Frequency Hopping Code Division Multiple Access (FH-CDMA) is a basic modulation technique used in spread spectrum signal transmission. FH-CDMA is the repetitive switching of frequency at the time of radio transmission. Advertisements This helps to reduce the strength of electronic warfare, that is...