CROSS JOIN with table that has no row In definition; 

SELECT * 
from T1, T2


Cross Join: If T1 has N rows, T2 has M rows, the result set will have N x M rows.

If T2 has no row, then result of the JOIN has no row also. 

However, I want N rows (from T1), what can I do?

Any suggestion?

Note: I want cartesian product, there is no shared column between the tables.
You can't use CROSS JOIN if any of both sets has no rows for the output you want. You can simulate this behaviour with a FULL JOIN with an always true condition.

SELECT 
    * 
FROM
    T1
    FULL JOIN T2 ON true