Tuesday, February 19, 2019

The evolution of cellular mobile technology (from 1G to 5G)

Do you still remember the first generation of mobile phone running on 1G analog cellular telecommunication network? The phone is as bulky as a brick with large external antenna. The average talk time for each battery recharge is about 35 minutes only. It was a luxury item.

Mobile phones started to become popular during the 2G digital era, whereby SMS text messages were made possible. Sending SMS at that time was not as convenient as today, as the phones were having physical T9 keypad, and typing alphabets would need more than one strokes.

Apple has changed the world during 3G era by introducing iPhone supported with iTune app store. Physical keypad was totally removed from the phone, giving larger space for its touch screen.

Today we are at 4G era, moving forward to 5G soon.

The table below summarizes the evolution of cellular mobile technology from 1G to 5G. We can see that for each advancement of generation, or sub-generation in between, there would be an increase in data transfer speed, and wider range of network application usage.

5G will be essential for the IoT connected world, particularly for connected vehicles and smart cities.

5G technology promises to greatly reduce the latency (the "preparation time" required before 2 wirelessly connected device to start transmitting data to each other) to around 1 milliseconds, compared with the current 30 milliseconds in 4G LTE.

5G technology also promises a 20 times increase in network speed from 4G, bringing gigabit Internet access possible to all mobile devices.

5G technology also promises a much stable and reliable signal strength by utilizing massive MIMO beamforming technology, which is a matured technology already in used in Wireless-AC WiFi networks for years.

On the other hand, 5G will require much stronger end-to-end cybersecurity protection and user privacy protection.

Are you excited to the upcoming 5G technology? It is said that key industry players are already working on 6G, which will mesh over satellite WiFi technology.

Monday, February 18, 2019

EPF declared 6.15% (conventional) / 5.90% (shariah) dividend for 2018

The Employees Provident Fund (EPF, a.k.a. KWSP) has just declared the dividend rate for financial year 2018.

For year 2018, the dividend declared for conventional account is 6.15% while for Shariah account is 5.90%. The dividend has already credited into members' account, and you can check for it by login into your EPF i-Account.

Year 2018 was the second year of dividend declaration for Shariah account, while dividend for conventional account has been declared annually since 1952. The dividend for Shariah account in both 2017 and 2018 were lower than the dividend for conventional account of the same year.

The 6.15% dividend for EPF conventional account in 2018 is 10.87% lower than the 6.9%  dividend declared for 2017 (last year).

Calculation: (6.15-6.90)/6.90 = -0.75/6.90 = -10.87%

It is 4.24% higher than the 5.90% Shariah dividend declared for the same year.

Calculation: (6.15-5.90)/5.90 = 0.25/5.90 = 4.24%

You can click here to check the historical EPF dividend pay-out rates from 1952 until today to judge yourself whether the dividend payout rate in 2018 is satisfactory or not.

Tuesday, February 12, 2019

Smart devices Li-polymer battery fast charging technology and compatibility

Nowadays, one of the selling points of smart devices (phones, tablets, watches, cameras, etc.) is how soon can they recharge their Li-polymer battery. There are already products which claim to be able to recharge from 10% to 100% within 20 minutes.

The battery charging speed is an important convenience indicator. If your mobile device can recharge its battery within a short period of time, it will greatly reduce your waiting time for its battery recharging, and also reduce the need of bringing along a power bank.

Imagine that when you are on the move and taking a short break at a place, you just need to borrow a power source for 5-10 minutes to quickly recharge your phone to bring up its battery level to be sufficient for the rest of the day, there will be less worry for you about the phone running out of battery power, and you don't need to wait for a long time for the recharging process.

The Li-polymer battery fast charging technology evolves following the evolution of USB into Type C era, and the introduction of industry standard called USB Power Delivery (USB-PD).

Traditionally, the USB cable has more emphasis on data transfer than charging function. The maximum power or Wattage (Power = Voltage x Current) a traditional USB cable and its charger can deliver is merely 2.5W.

With the current USB 3.1 standard, theoretically the maximum charging power can go as high as 100W. The more wattage the charging mechanism can deliver, the faster will be the charging process.

The charging mechanism consists of:
  • The charger
  • The cable
  • The device (phone/tablet/etc. for non-removable battery)
  • The battery
For fast charging to happen and to be safe, all the 4 charging components must be compatible and working well with each other. Otherwise, you will probably end up with traditional 2.5W slow charging, or your fast charging will be at risk of overheat, overcharge, battery damage or even device damage.

Compatible fast charging components will form a charging mechanism that can deliver stable fast charging wattage, and has electronic circuits and mechanisms to protect the battery and device from being damaged (such as catching fire, explode, bulking, malfunction, ...), overheat, overcharge, etc.

Different device manufacturer has come out with different kinds of fast charging mechanism, under different brand names such as Quick Charge, TurboPower, Pump Express, SuperCharge, VOOC, and so on.

If the device and battery is USB-PD compliance, then you can fast charge it with 3rd party or other brand of USB cable and/or charger that are also USB-PD compliance.

If the device and battery is Qualcomm Quick Charge compatible, then you can fast charge it with 3rd party or other brand of fast charger with Qualcomm Quick Charge chipset inside, using USB cable that supports 5A current transmission.

If you want to play safe, the rule of thumb is to fast charge your device using original charger and original cable from the same manufacturer designed for your device.

It seems that Oppo Super VOOC can charge its supported Oppo phones more faster than the others, however the Super VOOC charging mechanism is pretty proprietary. Huawei SuperCharge 2.0 found in its Mate 20 Pro, Mate 20X and later model of devices can also charge pretty fast at 40W, and is compatible to USB-PD and Qualcomm Quick Charge, although the wattage might be lower when fast charged with 3rd party compatible charger and cable.

Here are some tips if you want to buy a power bank, 3rd party charger or 3rd party USB cable:
  • Choose the USB cable that can support 5A charging. It is backward compatible and more future proof.
  • Choose the power bank that support Quick Charge 3.0 or Quick Charge 4.0+ to enable fast charging with compatible devices. Make sure it also has built-in mechanism to protect the battery and device properly. Choose for branded product that is reliable.
  • Choose the wall charger that support the same charging voltage and current with your original wall charger. Make sure it also has built-in mechanism to protect the battery and device properly. Choose for branded product that is reliable.

Hint: Click on the "Older Posts" link to continue reading, or click here for a listing of all my past 3 months articles.