your IELTS score now is good enough. Though there is a concern, your 12th year of education is in Arts and then BCA. Hope your BCA was a regular, one. But your percentage over all is good to go. Now, project management course in Sheridan is good for you to go. Sheridan is just 30 to 40 odd kms from humber. Even if you make it in sheridan, you can always move to different program. Though this 6 months program you talked about in Chandigarh can certainly help you boost your application for wireless, though ZCC is not accredit for 1 year regular programs but are good at providing hands on experience as their ties with industries are good (this is my own opinion, i may be wrong, please consult other sources too). However, CHC considers any one year diploma or certificate. Yet, if you are really really interested, seriously interested in wireless only, I would say you wait for Humber's response and in the mean time, make a very strong SOP mentioning why this wireless program, why Canada...
Wish you Luck brother.
Cheers!