Six months after the company launched a joint venture with Nokia, Siemens’ new Chief Executive Officer Peter Loescher said he is dissatisfied with the results.

"We are absolutely not satisfied with NSN," Loescher said in a press conference this week, referring to Nokia Siemens Networks.

In an August research note, RBC Capital Markets analyst Mark Sue said NSN’s equipment sales were “struggling a bit,” estimating its second-quarter revenue at 3.4 billion euros, or about $4.8 billion.

“Nokia is back-tracking on its double-digit margin target for this division, as competitive pressures intensify from Ericsson and Huawei [Technologies],” Sue said, adding that NSN was accelerating its plan to achieve cost synergies. The goal of realizing 1.5 billion euros in savings by 2010 was recently pushed up to 2008.

Rumors surfaced this summer that NSN may have been among suitors considering an acquisition of Tellabs. But expectations for such a deal dampened as NSN and other potential acquirers reported tough second quarters.

In July, NSN named former Nortel Networks executive Sue Spradley to lead its U.S. operations. The company’s focus on GSM technology in North America puts it in the shadow of more popular CDMA. It supplies legacy gear to the two Tier 1 GSM providers here and has also built a portion of AT&T’s UMTS/high-speed packet access (HSPA) network—through a Siemens contract—as well as a similar network for T-Mobile—through a Nokia contract.