The pros and cons of WiFi frequencies 2.4GHz and 5GHz

Nowadays all WiFi access points (APs) or wireless network routers work on the 2.4GHz band of wireless frequency, while the newer dual-band devices also support the 5GHz band.

The WiFi standards that work on 2.4GHz band are:

• 802.11b (speed is up to 11Mbps)
• 802.11g (speed is up to 54Mbps)
• 802.11n (speed is up to 150Mbps for 20MHz channel width, 300Mbps for 40MHz channel width)

The WiFi standards that work on 5GHz band are:

• 802.11a (speed is up to 54Mbps)
• 802.11n (speed is up to 150Mbps for 20MHz channel width, 300Mbps for 40MHz channel width)
• 802.11ac (speed can reach 6.8Gbps with 8 antennas running at 160Mhz channel width)

For the dual-band WiFi AP or router, you can turn on either one of the frequency bands, or turn on both of them at the same time.

The pros / advantages of 2.4GHz band:

• Has a wider signal coverage area.
• Better penetration through walls and physical barriers.
• WiFi b/g/n supported by all wireless devices

The cons / disadvantages of 2.4GHz band:

• As most of the WiFi devices are using this band, it could be congested with a lot of interference if there are a lot of WiFi devices nearby.
• Out of its 13 available channels, only Channel 1, 6, 11 are not overlapping.
• Might get interference from microwave ovens, Bluetooth devices, wireless keyboard/mouse, cordless phones, etc. which are also operate on 2.4GHz frequency band.

The pros / advantages of 5GHz band:

• At the mean time, few WiFi devices are using this band, so it is less congested with much lesser interference.
• Has 23 non-overlapping available channels.
• Supports much higher network speed with 802.11ac standard.

The cons / disadvantages of 5GHz band:

• Has smaller signal coverage area.
• Poor penetration power through walls and physical barriers.
• Older wireless devices might not be able to work on this band.
• Might get interference from radar which also operates on 5GHz frequency band.

Below is the WiFi signals detected in a shopping mall. You can see how congested is the 2.4GHz band and how clear is the 5GHz band. Congestion and interference can cause wireless connection problems such as intermittent connection lost, slow speed, unable to establish connection with AP, etc.

I am sure you will get similar result at your office or in your residence when your neighbours are also using WiFi.

If you have mobile devices that can work on 5GHz band and you have a dual-band AP/router, you might probably want to turn on both of them to get the best of both worlds.

Auspicious dates for ground-breaking of new building construction in 2014

Here is the list of auspicious dates in year 2014 for ground-breaking ceremony (动土) of new building construction. It is produced based on the Chinese almanac Tong Shu. (Click the image to enlarge)

Bear in mind that although the Tong Shu is a compilation of Chinese astrology and calendaring studies gathering wisdom of thousands of years, we should use it wisely and rationally, but not be too superstitious on it.

You might probably be interested to also find out the auspicious dates in 2014 for:

• Wedding / Marriage
• Marriage proposal / engagement
• Renovation
• Moving to new house/office
• Housewarming / Open house / Party / Gathering
• Business opening
• Signing contract / register for marriage / receive baptism
• Start new job / assignment
• Baby first haircut (Mundan)
• Getting baby / conception planning / Caesarian delivery

You might probably be interested to also find out for:

• Inauspicious dates to avoid for wedding/marriage in 2014
• Auspicious dates for wedding/marriage in 2015
• Inauspicious dates to avoid for wedding/marriage in 2015

The historical relationship between FIFA World Cup and stock market performance

The 2014 FIFA World Cup soccer tournament will take place in Brazil from 12 June until 13 July 2014. Have you wonder what will be its immediate impact to the stock market before, during, and after the tournament?

Based on historical charts of Dow Jones and KLCI from 1990 until today, I have summarized the stock market performance in US and Malaysia during the years with FIFA World Cup, for the short period of early May to end July. The FIFA World Cup normally held in summer of northern hemisphere (around June) and last for about a month.

Here is the summarized chart (click to enlarge):

Based on historical stock market performance, in the US market, there is equal chance to be sideline (yellow box), trending up (green box), or trending down (red box) before and during the FIFA World Cup tournament. After the tournament, it is very likely to go down. Historically from 1990-2010, only 2006 US market goes up after the tournament.

For the Malaysian stock market, it has high chance of going down before the tournament, sideline during the tournament, and going up after the tournament.

These are the considerations during the FIFA time which might affect the stock market performance:

• Retail participants in stock market might allocate their time and money to football gambling, therefore temporary gone out of the stock market.
• In Malaysia, as FIFA held in western host country happens at mid-night, the market participants who watch the matches during mid-night might be sleeping during market opening time, or not having enough concentration to the market.
• The FIFA news will overwhelm other news, including industry and business news.

So, what will happen to the stock market this year around FIFA time? Let's wait and see.