Would anyone know how many antennas do most smartphones have ?
Thank you
Not sure if this applies directly to your question...
I installed a Wifi card in my computer. Looking at the outside of it, there is only one hinged plastic rod visible.
However the Link Status monitor has three status bars for reporting signal strengths. This suggests it has 3 antennas, or else 3 receivers.
Normally it shows levels for signals 1 and 3. I don't remember it ever indicated a level for signal 2. Reason unknown.
It depends on cellphones Some have one antenna (old cellphones). But nowadays, we find cellphones with 2 or 3 antennas as far as i know. One for the communication for calling, one for the wifi and one for bluetooth.
Besides GSM antenna, WiFi and BT, can the phone contain 2 or 4 antennas for LTE, a GPS antenna, NFC, RFID and some do also contain internal antennas for FM radio and TV. A few phone models have internal ferrite antenna for AM radio reception.
Same antenna be shared for both WiFi and BT but it is not common. WiFi can have more than one antenna. For FM can the phone have one additional antenna for TX.
Wireless charging do also require a kind of antenna, even if it not is used for communication.
A basic phone have just one antenna, but it is often a multiband antenna, covering 2-5 frequency bands.
Thanks to all replies very helpful indeed. After reading the replies I would like to ask just a couple of more questions. Anyone wishing to reply please feel free. If a present day smart phone have multiple antennas for say Voice, Data, Wi-Fi and Bluetooth each then how many IC transceiver or receiver chips will the smart phone have ? Will the smart phone have one transceiver or receiver chip one for each antenna or type of communication or will there be just a single transceiver IC chip for all of the types of communication such as Voice, Data, Bluetooth and Wi-Fi ? Personally I think there is just the one IO controller or transceiver chip performing all of the above types of communications. Please correct me I am wrong in my opinion having multiple receiver or transceiver chips will take up more space on the PCB assembly and would not be practical. Lastly can multiple antennas co-exist on such a small PCB of a smart phone without running into interference from one another ? I've read about a coupling effect somewhere of having multiple antennas.
Thanks again to all those who have replied.
Victor
Number of IC's varies. It exist combined chips that for example provide FM radio and BT, or BT and WLAN. GSM and LTE in separate chips or partly combinations exist. GPS have not much in common with other systems so it would not be any gain to combine it with another radio system. So far does it not exist one single super chip that can handle all frequencies, bandwidths, modulation types for both Tx and Rx and optimize its function to provide best power efficiency for any Tx power level. Some systems are frequency hopping and some use different band for Tx and Rx. A such universal chip can be compared with a vehicle that is optimized for climbing in trees and running at race tracks, at the same time. A related idea is the fully software defined radio system, where any Rx/Tx parameter can be defined or replaced by software. http://en.wikipedia.org/wiki/Software-defined_radio
Do not know what kind of IO-controller you is thinking about, a main CPU normally exist, most RF-chips have there own MCU and can be partly autonomous, for example when a FM radio have been activated and set up by main CPU, then can it continue deliver signal to speaker and deliver decoded RDS, without communicating with main CPU.
Antenna coupling effect exist and can require a lot of job to reduce, especially if system performance is depending on two antennas tuned for same frequency band, where the both antennas must have high internal isolation.
For antennas designed for different frequency bands, in frequency wide apart, is coupling a minor problem that can be solved by filtering either by antenna design or by external filters.
Nowadays just 3 or 4 chips can do all the jobs for the foresaid antennas.
Such as Qualcomm chips:
One MSMXXXX as modem&CPU&GPU etc.
One or two RF TRX chips for all the GSM, WCDMA, TDD/FDD-LTE, etc.
One chips for WLAN/BT/FM etc.
One power supply for DC power of the foresaid chips and Wireless charging control. That's all for a smart phone. Very easy in circuits.
Thank you Tony and E Kafeman. Would either of you or anyone else know which IC chip handles keyboard and touch screen input, sends data to the LCD, sends signal the speaker and so on ? @Kafeman this was the IO controller I was trying to describe. Thanks to all replies.
Victor
Tony is right, today can much of the functions be integrated in a single chip.
Guess it is the stuff I am working with that is a bit old fashion and still is built as one chip for each function.
You can read more about the by Tony proposed chip here: http://www.qualcomm.com/snapdragon/processors/800
That chip seems to have more functionality and better performance then my desktop computer.
Thanks to all replies again. @Kafeman with respect to the IO Controller that I mentioned in my previous post turns out to be the Microcontroller. Apparently this is the one and only chip that takes care of the IO. So any user input via keyboard or touchscreen and sends output to the LCD and same with sending audio to the internal speakers and so on. I would like to learn whether this chip comes with an embedded GPU ?
Thanks again.
Victor
<which IC chip handles keyboard and touch screen input, sends data to the LCD, sends signal the speaker and so on ? @Kafeman this was the IO controller I was trying to describe>
sensor link to MSMXXXX,
keyboard link to PMIC,
camera link to MSMXXXX,
display link to MSMXXXX,
Speaker route is: MSMXXXX-->PMIC power amplifier--> speaker