Denso BHT-202Q-CE Operator's Manual

Denso BHT-202Q-CE Operator's Manual Manual pdf 18 page image

14Using Radio LinkThe BHT-202QW-CE supports spread spectrum communication.• If there are too many communications errors, first make sure that theBHT-202QW-CE points directly at an access point because the 2.4-GHz bandrequires a more or less straight line path. Note also that the low-power radiowaves have trouble passing through human bodies and other obstacles along thatpath.• This link will not operate properly in the vicinity of microwave ovens, industrialheaters, high-frequency medical equipment, and other sources of radio waves inthe 2.4-GHz band.• Electromagnetic noise from personal computers, refrigerators, and other homeappliances can also interfere with link operation.• Environmental factors that can also interfere with link operation include largemetallic objects, metallic dust, or metallic walls in the vicinity of the path andvibration at either end.To System Designers:• Before developing the application, make sure that the intendedenvironment is free of the interference factors above and thus actuallycapable of supporting link operation.• Assume that there will be communications failures requiring robust retrycapabilities in the software.• When introducing the BHT link operation into an environment whereequipment using radio waves in the 2.4-GHz band operates or whenintroducing such equipment after the introduction of the BHT linkoperation, be sure to confirm that the BHT radio link operates properlywith all equipment being in operation beforehand.• If the environment of the radio communications system is changed afterthe introduction (e.g., newly installed household appliances andmovement/addition of shelves or objects), then confirm that the radio linkoperates properly again before the actual use.