A 61-year-old man has pleaded guilty to multiple sexual assaults on women in Sydney during the early 1990s after police made a breakthrough in a three-decade-old cold case.

Glenn Gary Cameron was arrested at Sydney International Airport last February after detectives reviewed the unsolved cases using modern DNA and fingerprint technologies.

Cameron has now admitted to more than a dozen charges, including 11 counts of aggravated sexual assault using a weapon as a threat, for attacks on eight women between 1991 and 1993.

Dubbed Sydney's "Night Stalker" and the "Moore Park Rapist" in news reports at the time, Cameron is due to be sentenced next month.

After his arrest at the airport last year, Cameron's identity was suppressed due to a reporting ban. It was lifted three months later.

Of the 36 offences he has been charged with, he pleaded guilty to 13 on Tuesday, when he appeared in Downing Centre Local Court in Sydney via a video link.

Nine charges were withdrawn and the remaining 14 charges will be taken into account when he is sentenced, according to the Australian Broadcasting Corporation (ABC).

The latter include multiple charges of indecent assault, aggravated sexual assault and detaining a person for advantage.

One of the women attacked by Cameron decades ago dialled into court proceedings, the ABC reported.

A 1993 article in the Sydney Morning Herald (SMH) newspaper, which closely covered the spate of attacks, reported that the victims were mainly Asian women, aged 17 to 45.

The article alleged that the attacker - who knew simple phrases in Cantonese - targeted many of his victims near train stations and tricked them with the offer of fake jobs. He would then reportedly attack them at knifepoint, usually at night.

The first attack was in April 1991, the SMH reported, in the inner-west suburb of Strathfield, with other attacks in Moore Park in the eastern suburbs.