Vent Pipe

How's everyone doing? I have a question about venting a shower in my basement. Right now I plan on placing a corner shower in the corner of the future bathroom. What I need to figure out is how to vent it. Here is the description of my problem.
-I have a waste stack that goes through the roof and down into the basement which serves my kitchen sink.
-There is a vent that comes off of the waste stack.
-In the basement, the waste stack goes straight down and into the basement floor.
-The Vent pipe has a 90 degree bend just below the 1st story floor joists (also has a T to connect to waste stack before it terminates in the floor).
-The vent stack travels below the floor joists to and connects to the vent for the basement sink.
-The floor joists run East-West, and the basement vent pipe is running North-South so it has to be below the joists.
-I would like to have my shower vent pipe hidden between the joists (running East-West) and connect across the room to the Vent pipe that is already in the basement (running N.-S.) so the new shower vent pipe does not run in front of the only window in the bathroom.
My Question:
-When the new vent pipe gets across the room, can I put a 90 to turn the new vent pipe down and connect it to the existing vent with a T? (This picture shows a side view and is referencing the East-West view. You would have to imagine where the larger black dot of the existing vent pipe would be running towards you in the North South direction).


Does this make sense? This is all done so I can basically get the new vent pipe hidden from view within the joists, but I'm not sure if I can turn it downwards to connect with the existing vent. Thanks for all of the help!

That vent pipe has to have upward pitch or run level (UPC) it can't be turned down, sorry.

The major factor here is where the vent is connected to the stack. To use the existing stack vent, the shower vent must be connected at least 6" above the flood rim of the kitchen sink, assuming it is the highest connected fixture. Turning the vent downward essentially creates a broken vent.

cacher_chick, right now the vent and main stack for the kitchen sink both run parallel as they come through the main floor into the basement. Then the waste line goes straight down into the basement floor connecting to the main waste line for the house. The vent line that comes into the basement takes a 90 and travels about 6 feet just under the joists to connect to the basement sink vent.
The waste line and vent line that I'm talking about connect to each other about 3 feet above the kitchen sink with no other fixtures above it.

shacko - My thinking was that since the vent line tied into the waste line above the highest fixture (kitchen sink), that adding the shower would not interrupt the air flow. I can understand that there shouldn't be any drops. What if I tied into the vent line at the same level I was running shower vent line (no drops)? I would have to drill a hole through the joist, connect a T to the vent line, and just below the new T, would be the existing 90 bend that would continue to vent the existing bathroom sink. Does this make sense?

If this would work, could I vent the shower with 1 1/2" pipe (so I can drill a smaller hole through the joist),, or should I remain at 2". Thanks again for all of the help, you guys are great and very informative!

Added Pictures

Here are some pictures of what I already have going on.