Is antennas are applicable for wireless modes?

<font color=#550066>Suitable antennas <h2></h2></font>are required to the success of low-power wireless application. There are some key points on applying the antennas:
i. Antenna should be placed on the outside of the product. And try to place the antenna on the top of the product.
ii. Antenna can’t be placed inside a metal case because of its shielding effect.
iii. Antenna design involves expensive test equipments such as vector network analyzer and calibrated test antenna. Unless you have access to these equipments, the use to an antenna consultant is recommended.
iv. In most indoor locations, dead spots can be found where reception is difficult. These dead spots are due to multiple transmission paths existing between two points because of reflections off metal objects such as steel beams or metal doors. They happen when the path lengths effectively differs by an odd half-wavelength. This explains the phenomenon when you find that at some locations the reception effect is very poor, but beyond that the reception becomes normal.
v. 50-Ohm antenna is recommended for the best matching.
vi. For 433.92MHz application, antenna length = 17 cm.