Softening up the handset
Published: 9 January, 2008
READ MORE: Handset
With the sophistication of today's mobile phones it is easy to forget that the handset, at heart, is a radio: the phone's basic function is to send and receive radio signals carrying voice or data information. These signals travel on different frequencies, utilising various waveforms. Traditionally, radios have been implemented entirely in hardware, consisting of an antenna, RF front-end (amplifiers, receiver, transmitter) and baseband. New waveforms have been added by integrating new hardware.
However, over the years, the number of radios and wireless standard which a handset supports has grown tremendously. Looking at my own phone, which has been on the market for almost a year, it supports nine wireless standards - GSM, GPRS, EDGE, WCDMA, HSDPA, Bluetooth, Wi-Fi (802.11b and g) and GPS - and five different radio frequencies. Jump forward two or three years and its foreseeable that a mid-range handset sold into developed markets will need to support all the following wireless standards: GSM, GPRS, EDGE, WCDMA, HSDPA, LTE, GPS, mobile TV, Wi-Fi, Bluetooth, FM radio and UWB. Add WiMAX to the mix and the number of waveforms which a phone will need to support is mind-blowing - something has to give.
| Technology | Frequency |
| Bluetooth | 2.4GHz |
| FM radio | 87.5 - 108.0 MHz |
| GPS | 1.1 - 1.6GHz |
| GSM (GPRS, EDGE) | 900MHz, 1800MHz |
| Mobile TV (MediaFLO, DVB, DMB) | 200 - 800MHz |
| NFC | 13.56 MHz |
| UMTS (WCDMA, HSPA, LTE) | 2100MHz |
| UWB | 3.1 -10.6GHz. |
| Wi-Fi | 2.4GHz, 5.8GHz |
| WiMAX |
