It has been almost a hundred years since the birth of the walkie-talkie, half a century before the invention of the mobile phone. But in the last century, mobile phones have evolved from the former “big brother” to today’s smart phones, and the walkie-talkie is still the same stupid, black and thick old one, and the antenna is still external. So is the external antenna of the walkie-talkie due to technical bottlenecks or deliberately?
The walkie-talkie uses an external antenna
First of all, walkie-talkie is a kind of radio communication equipment, and the radio that this equipment relies on has a very important indicator called “working frequency”. The working frequency of domestic mobile phones has national standards, and mobile phones generally operate between 900MHz and 1800MHz. Communicate on two frequencies, and the state stipulates that the working frequency of public walkie-talkies (ie, civilian walkie-talkies) is between 409 and 410 MHz.
Civil walkie-talkies have operating frequency restrictions
In order to transmit the radio signal as much energy as possible, the antenna needs to be designed to half the wavelength. The wavelength is equal to the speed of light divided by the frequency. The higher the frequency, the longer the wavelength. In other words, the wavelength of a mobile phone is more than half smaller than that of a walkie-talkie. However, when designing an antenna, it is impossible to design the antenna to be as long as the wavelength, but the longer the better.
Of course, mobile phone design cannot blindly pursue signal priority. After all, the current mobile phone is a necessity, and there is only one hand. The iPhone 4 started to make the appearance of the mobile phone beautiful, so many mobile phone manufacturers will put the mobile phone antenna into the body. The interior or the outer shell is integrated, which can please consumers more. After all, people are visual animals, and good-looking things can naturally sell better.
The stainless steel frame of the iPhone 4 is the phone antenna
In the early days of Big Brother’s era, the antenna was externally mounted. On the one hand, the priority of the mobile phone design was not as high as it is now. On the other hand, the mobile phone signal coverage at that time was not as good as it is now. The wireless signal used by the mobile cellular network works The frequency is not as high as it is now, and the signal enhancement that a larger antenna can bring is obvious, so the mobile phone antenna in the big brother era was external, or even retractable.
Early Mobile Phone with external antenna
The antenna design requirements of the walkie-talkie are similar to the design requirements of the early Mobile Phone. Since the use scene of the walkie-talkie does not have high requirements for the appearance of the walkie-talkie, the priority of the appearance design is lower than the priority of the antenna design. Moreover, the operating frequency of the walkie-talkie is much lower than that of the mobile phone, and a larger and longer antenna is needed to send the signal better.