Advantages of telephone

1. Wireless Internet access: CDMA 1X or 3G(WCDMA, CDMA-2000, TD-CDMA) networks or even 4G(HSPA+, FDD-LTE, TDD-LTE) networks need to support GPRS under GSM networks.

2. It has the functions of PDA, including PIM (Personal Information Management), schedule, task arrangement, multimedia application and web browsing.

3. Open operating system: With independent core processor (CPU) and memory, more applications can be installed, and the functions of smart phones can be expanded infinitely.

4. Humanization: The machine functions can be expanded according to individual needs. According to personal needs, real-time expansion of the built-in functions of the machine, as well as software upgrade and intelligent identification of software compatibility, realize the humanized function of software market synchronization.

5. Powerful: strong expansibility and more third-party software support.

6. Fast running speed: With the development of semiconductor industry, the core processor (CPU) develops rapidly, which makes the smart phone run faster and faster.

7. Smartphones have Internet access and strong multimedia functions. You can browse the Internet, play audio and video, and have the functions of e-books and electronic photo frames. At the same time, the functions of smart phones in supporting office, marketing and entertainment have been greatly enhanced. On the basis of subverting the traditional fixed telephone, more business functions and PDA functions are realized.

Extended data

Technical performance of telephone:

1, working frequency: 300 ~ 3400HZ；;

2. Pulse on-off ratio:1.60.2:1;

3. Frequency offset of dual-tone dialing: ≤1.5%;

4. Dual audio signal level: ① Low frequency group:-93dB; ② High frequency group:-73dB; ③ The high frequency component in the frequency combination is 21db higher than the low frequency component;

5. Ringing level: ≥ 70dB (a);

6, electroacoustic performance:

(1), at 0 km, objectively send reference equivalent ≥+3; Within 3 km, the objective transmission reference equivalent is ≤+15; At 5km, the objective transmission reference equivalent is ≤+ 15.

② At 0 km, the objective reception reference equivalent is ≥-5; Within 3 km, the objective reception reference equivalent is ≤+2; At 5km, the objective acceptance test equivalent is ≤+2.

③ At 0 km, the objective transverse acoustic reference equivalent is ≥+3; At 3 km, the objective lateral sound reference equivalent is ≥+10; At 5km, the reference equivalent of the target sidetone is ≥+ 10.

Baidu encyclopedia-telephone

Baidu encyclopedia-smart phone