High-frequency waves have shorter wavelengths and vice versa
Longer wavelengths (such as radio waves) have low energy; this is why we can listen to the radio without any harmful consequences. Shorter wavelengths, such as X-rays, have higher energy, which can be harmful to our health.
High frequencies have short wavelengths and can be easily disturbed by the environment, but not for all media. Low frequencies have longer wavelengths and can diffraction around obstacles and can carry longer distances (this is not correct for all media). This is very similar to taking a straight line and coiled wires and trying to get them through the hole. Obviously, it is easier to pass through a straight line than coiled wires.
High-frequency waves carry more data than low-frequency waves because the amount of data that can be transmitted (i.e. bandwidth) is proportional to the frequency of the wave. High-frequency waves essentially have more rope shaking and can carry more data at the same time compared to low-frequency waves. In short, longer wavelengths propagate further, but less information is available. Shorter wavelengths have shorter ranges, but can carry more information.
Longer wavelengths have lower frequencies; shorter wavelengths have higher frequencies. (For reference, extremely low frequency (ELF) wavelengths exceeding 100,000 km, only a few cycles per second, or even less than one cycle, thus “extremely low” frequency. Gamma rays are about one trillion meters long (chart), with a full 50 million cycles per second. All of these waves travel (almost) at the speed of light.
Radio wave spectrum from low to high frequency
The wavelength range of radio waves ranges from 1 mm to 100 kilometers. High-frequency signals require lower antenna lengths, which is crucial for the phone. However, high-frequency signals are more sensitive to reflection and can make passing walls and obstacles more difficult. However, they can leak through holes of wavelength size.
Frequency and power determine cell size
Higher frequencies in the spectrum (more Hertz) are able to carry more information per second, rather than lower frequencies, but are not as reliable as lower frequencies over longer distances. Therefore, while higher frequencies can serve more customers per cell, using lower frequencies is smaller than the cells. This means that as the carrier uses a higher and higher part of the spectrum (which will be important when we reach 5G), the cell size will decrease, resulting in more cells and more antennas. The cell size also depends on the power of the transmitter, so for any given frequency band there may be larger or larger cells. The cells using small bands must be small, because millimeter waves are most effective in short distances, line of sight environments.
When the signal radiates into space, the power decreases the square of the distance and the path loss increases the distance traveled. For example, if you transmit two signals of equal power, one at 1 GHz and the second at 2 GHz, the 2GHz signal will fade into the noise 4 times faster (1/(2^2)) than the 1GHz signal and will propagate 1/4 before fade into the noise.
For shorter wireless links, their maximum power is limited by the FCC, which helps prevent wireless systems from interfering with each other and using other systems with the same or similar parts of the spectrum. However, these shorter wireless technologies use unlicensed spectrum, so a single device like your home router or wireless headset can run anywhere without the need to get FCC license in the first place. Bluetooth uses a narrow band of 2.4GHz, while WiFi (usually used for wireless local network marketing name [WLAN]operating according to the IEEE 802.11 protocol) some different frequency bands are used. Near Field Communication (NFC) is similar, but even shorter ranges (usually only a few centimeters) and supports things like contactless payment systems.
Radio waves are modulated using AM and FM
Modulation is an electrical technology used to apply information such as voice, music, images or data of radio frequency carrier waves by changing the wave performance or wave performance of smart signals. Amplitude, frequency, phase, pulse sequence and pulse length are the most conventionally regulated characteristics.
Radio signals are broadcast using AM (or amplitude modulation) and FM (or frequency modulation). In both cases, electromagnetic waves are used to transmit data. Based on the sent information, the amplitude (change) of the transmitted signal or carrier is modulated, but the frequency is still fixed. This is contrary to FM technology, which encodes information (music) by changing the frequency of the wave while keeping the amplitude constant.
The sound quality of AM is lower than that of FM, but it is cheap and can be broadcast over longer areas. Because it has a smaller bandwidth, it can accommodate more stations in any frequency range. Compared with AM, FM is less susceptible to interference. On the other hand, physical barriers have an impact on FM transmission. The bandwidth allocated to the FM station is 150 kHz, which is 15 times that of the AM station. This explains why music sounds much better on FM, because the FM station can send 15 times the message.
Hope this works, thanks.
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