"Even though I am utterly heartbroken that you had to leave us so soon, I feel so privileged and honoured to have been your wife," Mr Mason said.
Sen Const Rixon was shot in the chest and stomach after stopping a car in Lorraine Street, Tamworth, last week.
The man alleged to have shot him, Michael Alan Jacobs, 47, was also shot and remains at Newcastle's John Hunter Hospital.
Mr Scipione told the funeral service that Sen Const Rixon returned fire after being shot and even tried to handcuff Jacobs before collapsing.
The highway patrol officer died a short time later after being rushed to hospital.
His name will be etched onto the police wall of remembrance in Sydney, Mr Scipione said.
The wall, on Art Gallery Road, has around 250 names of police officers who have died in the line of duty.
Dozens of police officers, including Sen Const Rixon's closest colleagues, attended the service at St Paul's Anglican Church.
His wife and six children were also present, along with NSW Premier Barry O'Farrell.
A donation appeal for Mr Rixon's family has now reached more than A$200,000, with Mr O'Farrell contributing A$10,000 on behalf of the NSW Government.
- AAP